Now that I have your attention ...
Shame on you for thinking such a thing. 
You naughty reader, you!

Madame de Pompadour

Literature, poetry, and history—especially among the monarchy and at least one Pope—are full of stories of well-known kept women like Madame de Pompadour (originator of the pompadour hairstyle, a "Snookie" in the front, instead of in the back), the "pretty, witty Nell" Gwyn (one of the first English actresses), all the way down to Julia Roberts' role as call girl-turned-kept woman in Pretty Woman.

 Historically, a kept woman was a man's mistress (whether or not he was married to another woman). The man would set his lover up in a house of her own, assume responsibility for her debts, give her an allowance, provide for all her needs in comfortable style. Before divorce was an option (and in countries where it still isn't considered socially acceptable) the practice was quite common.

Nell Gwyn

The role of a concubine is probably the closest thing to a kept woman in the Bible, and the Old Testament is filled with tales of men and their concubines. Solomon reportedly had 700 wives and 300 concubines. (Note: This did NOT turn out well for Solomon.)

Why, you ask, (I can hear you through the computer, you know) would I lay claim to the title of kept woman?
Here's why...

I will lift up my eyes to the hills—From whence shall my help come?
My help comes from the Lord, Who made heaven and earth.

He will not allow your foot to slip or to be moved;
He Who keeps you will not slumber.
Behold, He who keeps Israel will neither slumber nor sleep.
The Lord is your keeper;
the Lord is your shade on your right hand [the side not carrying a shield].
The sun shall not smite you by day, nor the moon by night.

The Lord will keep you from all evil; He will keep your life.
The Lord will keep your going out and your coming in from this time forth and forevermore.