Full Frontal Nerdity

I agree with you. I don't think a physical relationship in prison would work well between them, unless the story were just a drabble or a ficlet. And even then it wouldn't be very deep, wouldn't give any room to explore the characters, and they seem to be very workable, rich characters, especially Michael. The brother's relationship in the series opens a plethora of possibilities for their past, and honestly, I think you should take 'Michael's goldmine of an adolescence' and run with it. I really hope you do ^^