Jeez... what school did you go to? I thought I had it tough growing up next to NYC projects!

I know it seems unoriginal that S.H. keeps raping people, but it's rape. It's probably the most cruel one-time thing to be done to a person, totally damaging both physically and mentally. If it helps, think of how the Forsaken think themselves above everyone, and then are physically degraded in the worst possible way. It's a fairly atrocious thing done to them.
Also, why it's a repeated punishment, it's never said that it's the only punishment they receive.