Any human who sells his sister (or indeed, any woman or other man) is irredeemable, and using someone as collateral for gambling debts IS selling them. He should be kicked to the curb and left to starve in a ditch. I don't care how stupid and naive he is, what he did comes under the category of unforgivable. The crooked, filthy saloon/brothel keeper should be hanged from the nearest tree, as well. Someone turning an inexperienced and terrified girl over to men as a sexual commodity is a class of person that is breathing air that could nourish a colony of slime mold, which is several rungs higher on the moral ladder than he is. The blatant misogyny of the setting of this story really got under my skin.
As Good As Gold