So what's an extragal?

Should and why should any of us particularly older guys legitimately and honorably search for, acquire, possess, and erotically integrate with one?

It behooves the best of us to study some Scriptural basis before the quest begins.

First Chronicles 2:21 Afterward Hezron went in to the daughter of Machir the father of Gilead, whom he married when he was sixty years old; and she bore him Segub....

First off, why the need? One answer is: "Why not?"

Consider the case of the "old geezer" Boaz:

Ruth 3:1 Then Naomi her mother-in-law said to her, "My daughter, should I not seek a home for you, that it may be well with you?
10 And [Boaz, not Bozo] said, "May you be blessed by the LORD, my daughter; you have made this last kindness greater than the first, in that you have not gone after young men, whether poor or rich.
11 And now, my daughter, do not fear, I will do for you all that you ask, for all my fellow townsmen know that you are a woman of worth.
16 And when she came to her mother-in-law, she said, "How did you fare, my daughter?" Then she told her all that the man had done for her....

It is interesting to note that Ruth was a Moabitess widow without record of ever having any children by her first husband:

Ruth 1:1 In the days when the judges ruled there was a famine in the land, and a certain man of Bethlehem in Judah went to travel in the country of Moab, he and his wife and his two sons.
2 The name of the man was Elimelech and the name of his wife Naomi, and the names of his two sons were Mahlon and Chilion; they were Ephrathites from Bethlehem in Judah. They went into the country of Moab and remained there.
3 But Elimelech, the husband of Naomi, died, and she was left with her two sons.
4 These took Moabite wives; the name of the one was Orpah and the name of the other Ruth. They lived there about ten years;
5 and both Mahlon and Chilion died, so that the woman was bereft of her two sons and her husband.
6 Then she started with her daughters-in-law to return from the country of Moab, for she had heard in the country of Moab that the LORD had visited his people and given them food.
7 So she set out from the place where she was, with her two daughters-in-law, and they went on the way to return to the land of Judah.
8 But Naomi said to her two daughters-in-law, "Go, return each of you to her mother's house. May the LORD deal kindly with you, as you have dealt with the dead and with me.
9 The LORD grant that you may find a home, each of you in the house of her husband!" Then she kissed them, and they lifted up their voices and wept.
10 And they said to her, "No, we will return with you to your people."
11 But Naomi said, "Turn back, my daughters, why will you go with me? Have I yet sons in my womb that they may become your husbands?
12 Turn back, my daughters, go your way, for I am too old to have a husband. If I should say I have hope, even if I should have a husband this night and should bear sons,
13 would you therefore wait till they were grown? Would you therefore refrain from marrying? No, my daughters, for it is exceedingly bitter to me for your sake that the hand of the LORD has gone forth against me."
14 Then they lifted up their voices and wept again; and Orpah kissed her mother-in-law, but Ruth clung to her.
15 And she said, "See, your sister-in-law has gone back to her people and to her gods; return after your sister-in-law."
16 But Ruth said, "Entreat me not to leave you or to return from following you; for where you go I will go, and where you lodge I will lodge; your people shall be my people, and your God my God;
17 where you die I will die, and there will I be buried. May the LORD do so to me and more also if even death parts me from you."
18 And when Naomi saw that she was determined to go with her, she said no more.

And where did Moabitess Ruth originate from?

Genesis 19:36 Thus both the daughters of Lot were with child by their father.
37 The first-born bore a son, and called his name Moab; he is the father of the Moabites to this day.
38 The younger also bore a son, and called his name Benammi; he is the father of the Ammonites to this day.

In addition to that, the primary woman in our lives we certainly love, as Abraham loved Sarah (by whom he produced Isaac) more than he concurrently loved Hagar (by whom he produced Ishmael)....Jacob loved Rachel (who bore him Joseph and Benjamin) more than he concurrently loved Leah (who bore him Reuben, Simeon, Judah, ) and concurrently loved Bilhah (who bore him Dan and Naphtali) and concurrently loved Zilpah (who bore him Gad and Asher)....and Elkanah loved Hannah more than he concurrently loved Peninnah.....David loved Bathsheba (by whom he produced King Solomon) more than he concurrently loved Ahinoam (who bore him Amnon), Maacah, and Nabal's widow Abigail (by whom he produced Chileab, and there is no record of Abigail having sex with Nabal nor ever producing any children by Nabal) and his concubines....Solomon loved the Shunammite (by whom he produced King Rehoboam) more than he concurrently loved the other 999 wives and concubines he had.....and Hosea loved "Gomer" more than the [other?] woman he bought later on.

With reference to that other? woman:

Hosea 3:1 And the LORD said to me, "Go again, love a woman who is beloved of a paramour and is an adulteress; even as the LORD loves the people of Israel, though they turn to other gods and love cakes of raisins."
2 So I bought her for fifteen shekels of silver and a homer and a lethech of barley.
3 And I said to her, "You must dwell as mine for many days; you shall not play the harlot, or belong to another man; so will I also be to you."

Many commentators have taken the above quotation to mean that Gomer, who apparently bore Hosea two sons and one daughter, was wayward and left him to play the harlot with others, after which Hosea bought her back at some kind of slave-women auction. I take it to perhaps mean that that other adulterous woman was a totally different woman other than Gomer, just as the LORD accepts both penitent-but-previously-defiled Jews and penitent-but-previously-defiled Gentiles.

When Jesus Himself was confronted by Sadducees proposing a rather off-the-wall hypothetical scenario about a woman being married to seven brothers and then asking whose wife she would be in "the resurrection," notice that Jesus did not state that she would or would not be in a state of marriage with all seven, or only the first one, or whether she had sex with any of them or they with her, but rather:

Matthew 22:29 But Jesus answered them, "You are wrong, because you know neither the scriptures nor the power of God.
30 For in the resurrection they neither marry nor are given in marriage, but are like angels in heaven.
31 And as for the resurrection of the dead, have you not read what was said to you by God,
32 'I am the God of Abraham, and the God of Isaac, and the God of Jacob'? He is not God of the dead, but of the living."

Mark 12:24 Jesus said to them, "Is not this why you are wrong, that you know neither the scriptures nor the power of God?
25 For when they rise from the dead, they neither marry nor are given in marriage, but are like angels in heaven.
26 And as for the dead being raised, have you not read in the book of Moses, in the passage about the bush, how God said to him, 'I am the God of Abraham, and the God of Isaac, and the God of Jacob'?
27 He is not God of the dead, but of the living; you are quite wrong."

Luke 20:34 And Jesus said to them, "The sons of this age marry and are given in marriage;
35 but those who are accounted worthy to attain to that age and to the resurrection from the dead neither marry nor are given in marriage,
36 for they cannot die any more, because they are equal to angels and are sons of God, being sons of the resurrection.
37 But that the dead are raised, even Moses showed, in the passage about the bush, where he calls the Lord the God of Abraham and the God of Isaac and the God of Jacob.
38 Now He is not God of the dead, but of the living; for all live to Him."
39 And some of the scribes answered, "Teacher, you have spoken well."

The basic minimum for most red-blood men desiring sexual fulfilment is to have at least one woman to have sex with:

First Corinthians 7:1 Now concerning the matters about which you wrote. It is well for a man not to touch a woman.
2 But because of the temptation to immorality, each man should have his own wife and each woman her own husband.
3 The husband should give to his wife her conjugal rights, and likewise the wife to her husband.
4 For the wife does not rule over her own body, but the husband does; likewise the husband does not rule over his own body, but the wife does.
5 Do not refuse one another except perhaps by agreement for a season, that you may devote yourselves to prayer; but then come together again, lest Satan tempt you through lack of self-control.

The Holy Spirit's human authors, including Saint Paul, did not specifically forbid multiple-wife harem-type polygamy for all Christian males, but only for certain ones:

Leviticus 21:7 [The High Priest, or Pope] shall not marry a harlot or a woman who has been defiled; neither shall they marry a woman divorced from her husband; for the priest is holy to his God.
14 A widow, or one divorced, or a woman who has been defiled, or a harlot, these he shall not marry; but he shall take to wife a virgin of his own people....

Deuteronomy 24:1 When a man takes a wife and marries her, if then she finds no favor in his eyes because he has found some indecency in her, and he writes her a bill of divorce and puts it in her hand and sends her out of his house, and she leaves his house,
2 and if she goes and becomes another man's wife,
3 and the latter husband dislikes her and writes her a bill of divorce and puts it in her hand and sends her out of his house, or if the latter husband dies, who took her to be his wife,
4 then her former husband, who sent her away, may not take her again to be his wife, after she has been defiled; for that is an abomination before the LORD, and you shall not bring guilt upon the land which the LORD your God gives you for an inheritance.

Deuteronomy 17:17 And [the king] shall not multiply wives for himself, lest his heart turn away; nor shall he greatly multiply for himself silver and gold.

That, however, in view of:

Ecclesiastes 2:8 I also gathered for myself silver and gold and the treasure of kings and provinces; I got singers, both men and women, and many concubines, man's delight.

Matthew 19:3 And Pharisees came up to Him and tested Him by asking, "Is it lawful to divorce one's wife for any cause?"
4 He answered, "Have you not read that he who made them from the beginning made them male and female,
5 and said, 'For this reason a man shall leave his father and mother and be joined to his wife, and the two shall become one flesh'?
6 So they are no longer two but one flesh. What therefore God has joined together, let not man pull apart."
7 They said to Him, "Why then did Moses command one to give a certificate of divorce, and to put her away?"
8 He said to them, "For your hardness of heart Moses allowed you to divorce your wives, but from the beginning it was not so.
9 And I say to you: whoever divorces his wife, except for unchastity, and marries another, commits adultery."
10 The disciples said to Him, "If such is the case of a man with his wife, it is not expedient to marry."
11 But He said to them, "Not all men can receive this saying, but only those to whom it is given.
12 For there are eunuchs who have been so from birth, and there are eunuchs who have been made eunuchs by men, and there are eunuchs who have made themselves eunuchs for the sake of the kingdom of heaven. He who is able to receive this, let him receive it."

First Timothy 3:2 Now a bishop must be above reproach, the husband of one wife, temperate, sensible, dignified, hospitable, an apt teacher,
12 Let deacons be the husband of one wife, and let them manage their children and their households well;

Not much is said about which wives of the Old-Testament patriarchs were favorites:

Genesis 4:19 And Lamech took two wives; the name of the one was Adah, and the name of the other Zillah.
20 Adah bore Jabal; he was the father of those who dwell in tents and have cattle.
21 His brother's name was Jubal; he was the father of all those who play the lyre and pipe [included are those who play wind and brass instruments, plus string players and keyboardists].
22 Zillah bore Tubalcain; he was the forger of all instruments of bronze and iron. The sister of Tubalcain was Naamah.

Second Samuel 5:13 And David took more concubines and wives from Jerusalem, after he came from Hebron; and more sons and daughters were born to David.

First Chronicles 4:5 Ashhur, the father of Tekoa, had two wives, Helah and Naarah;

Second Chronicles 24:2 And Joash did what was right in the eyes of the LORD all the days of Jehoiada the priest. 3 Jehoiada got for him two wives, and he had sons and daughters.

Whatever the case, the polygamous patriarchs loved their primary wives more than their other wives and concubines, in accord with:

Malachi 2:15 Has not the one God made and sustained for us the spirit of life? And what does he desire? Godly offspring. So take heed to yourselves, and let none be faithless to the wife of his youth.

So why the need for not another let alone a different woman, but rather an additional wife or concubine(s)?

A few possibilities exist:

Genesis 1:28 And God blessed them, and God said to them, "Be fruitful and multiply, and fill the earth and subdue it; and have dominion over the fish of the sea and over the birds of the air and over every living thing that moves upon the earth."
9:1 And God blessed Noah and his sons, and said to them, "Be fruitful and multiply [so much for mandatory or forced sterilization and zero population growth], and fill the earth.

Deuteronomy 21:15 If a man has two wives, the one loved and the other disliked, and they have borne him children, both the loved and the disliked, and if the first-born son is hers that is disliked,
16 then on the day when he assigns his possessions as an inheritance to his sons, he may not treat the son of the loved as the first-born in preference to the son of the disliked, who is the first-born,
17 but he shall acknowledge the first-born, the son of the disliked, by giving him a double portion of all that he has, for he is the first issue of his strength; the right of the first-born is his.

[Such info would be useful in a theocracy to the Social Security Administration and the IRS concerning estate and probate court settlements involving State-licensed-and-registered multiple spouses].

Second Samuel 6:23 And Michal (or "Michelle" for a nickname) the daughter of Saul had no child to the day of her death [not only because she despised and reviled David, but perhaps also because she had sexually used by her other husband Paltiel, who longed for her].

Proverbs 21:9 It is better to live in a corner of the housetop than in a house shared with a contentious woman.
19 It is better to live in a desert land than with a contentious and fretful woman.
25:24 It is better to live in a corner of the housetop than in a house shared with a contentious woman.
27:15 A continual dripping on a rainy day and a contentious woman are alike;

Matthew 22:24 ....."Teacher, Moses said, 'If a man dies, having no children, his brother must marry the widow, and raise up children for his brother.'
Mark 12:19 "Teacher, Moses wrote for us that if a man's brother dies and leaves a wife, but leaves no child, the man must take the wife, and raise up children for his brother.

If the man has no brothers to marry his widow, she is better off to remain a widow rather than re-marry, per:

First Corinthians 7:39 A wife is bound to her husband as long as he lives. If the husband dies, she is free to be married to whom she wishes, only in the Lord.
40 But in my judgment she is happier if she remains as she is. And I think that I have the Spirit of God.

Romans 7:1 Do you not know, brothers (for I am speaking to those who know the law) that the law is binding on a person only during his life?
2 Thus a married woman is bound by law to her husband as long as he lives; but if her husband dies she is discharged from he law concerning the husband.
3 Accordingly, she will be called an adulteress if she lives with another man while her husband is alive. But if her husband dies she is free from that law, and if she belongs to another man she is not an adulteress.

First Timothy 5:11 But refuse to enroll younger-women widows [Gr. ne(o)teras and ch(e)ras]; for when they grow wanton against Christ they desire to marry,
12 and so they incur condemnation for having violated their first pledge.
14 So I would have younger women (the word for "widows" is NOT in the Greek Text here!) marry, bear children, guide their households, and give the enemy no cause to revile us.
15 For some have already strayed after Satan.

Regardless of how many wives or concubines a man has, they all require love and adequate sustenance:

Ephesians 5:25 Husbands, love your wives, as Christ loved the church and gave himself up for her....
Colossians 3:19 Husbands, love your wives, and do not be harsh with them [no verbal, physical, nor emotional abuse, please].

First Timothy 5:8 If any one does not provide for his relatives, and especially for his own family, he has disowned the faith and is worse than a disbeliever.

James 2:15 If a brother or sister is ill-clad and in lack of daily food,
James 2:16 and one of you says to them, "Go in peace, be warmed and filled," without giving them the things needed for the body, what does it profit?

What were and are the Christian requirements for an additional wife (or in our present American customs and jurisprudence: an additional common-law concubine, rather than a non-married mistress who is by definition a fornicator herself causing some non-married man to also be defined as a fornicator or some husband to be defined as an adulterer?

(1) She must be a bonafide Christian, not simply were a cross as a perhaps-meaningless ornamental necklace.

Ezra 10:11 Now then make confession to the LORD the God of your fathers, and do his will; separate yourselves from the peoples of the land and from the foreign wives.

Second Corinthians 6:14 Do not be mismated with disbelievers. For what partnership have righteousness and iniquity? Or what fellowship has light with darkness?

(2) She must be willing to covertly or overtly reconcile her married status as a common-law concubine with her father's family, his close relatives, and her friends.

Matthew 10:37 He who loves father or mother more than Me is not worthy of Me; and he who loves son or daughter more than Me is not worthy of Me;

Matthew 19:29 And every one who has left houses or brothers or sisters or father or mother or children or lands, for My name's sake, will receive a hundredfold, and inherit eternal life.

(3) She must be willing to perform whatever sexually-oriented actions her husband desires (such as fellatio), get pregnant, go through childbirth herself without committing abortion-homicide murder.

Deuteronomy 25:11 When men fight with one another, and the wife of the one draws near to rescue her husband from the hand of him who is beating him, and puts out her hand and seizes him by the private parts, 12 then you shall cut off her hand; your eye shall have no pity.Ephesians 5:24 As the church is subject to Christ, so let wives also be subject in everything to their [own] husbands.

First Timothy 2:12 I allow NO woman [inside OR outside of "the church"] to teach or to have authority over men; she is to keep silent [a polite way of saying: 'Shut up!'].
13 For Adam was formed first, then Eve;
14 and Adam was not deceived, but the woman was deceived and became a transgressor.
15 Yet woman will be saved through bearing children, if she continues in faith and love and holiness, with sobriety.

[NOTE: A few more references pertaining to men in authority over men, and not vice-versa per demonic "equal-rights" or "equal-opportunity" heresy, are:

Ecclesiastes 7:28 .....One man among a thousand I found, but a woman among all these I have not found.

Isaiah 3:12 My people: children are their oppressors, and women rule over them. Oh my people, your leaders mislead you, and confuse the course of your paths.

Nahum 3:13 Hey, your troops are women in your midst. The gates of your land are wide open to your foes; fire has devoured your bars.

First Timothy 5:14 (see KJV and Wesley NT) So I would have younger women marry, bear children, guide their households, and give the enemy no cause to revile us.

(4) Should should not be ashamed to admit (if necessary, though not on government nor government-related documents) that she belongs in common-law marriage as a concubine to a man she calls her husband, and which husband admits (if necessary, though not on government nor government-related documents) that the concubine indeed belongs to himself in common-law marriage.

Genesis 12:18 & Genesis 20:1-10 [approx] So Pharaoh/Abimelech called Abram/Abraham, and said, "What is this you have done to me? Why did you not tell me that she was your wife?

Mark 8:38 For whoever is ashamed of me and of my words in this adulterous and sinful generation, of him will the Son of man also be ashamed, when he comes in the glory of his Father with the holy angels."

(5) It would be helpful and convenient if she had her own job and aparment or house as a [married] concubine.

First Thessalonians 4:11 ....aspire to live quietly, to mind your own affairs, and to work with your hands, as we charged you;
12 ....command the respect of outsiders, and be dependent on nobody.

Galatians 6:5 For each [man] will have to bear his own load.

There are, of course, other qualifications one could and should consider, which will be left up to the innovative imagination of you the reader.

A final observation.

If you ever wanted to know how Christ Jesus (i.e. the Son of God, and therefore God Himself) would write a lovely romantic novel and respectable XXX sex dialogue - profuse with deep-meaning allegories and metaphors to avoid being pornographically titillating and licentuous - delve into The Song of Solomon, in which the Spirit of the Lord inspired Solomon to portray love between himself and his favorite woman out of a thousand, his beloved Shunammite.

Moreover, if you want to know how to best and decently describe explicit XXX details of harlotrous prostitution activity, study chapter 3 of the Old-Testament book of Isaiah, chapter 20 of Isaiah, chapter 47 of Isaiah, both chapters 16 and 23 of of Ezekiel, plus chapter two of both Jeremiah and Hosea.