Uhh, I'm not sure if I can explain it right since it's been a while since I last read the definition for it. I think--if I remember right--it's when a guy is obsessed with the idea of having a sister and, or, is obsessed with their sister. Hold up, let me Google this shiiiiz. Cx
Okay, I was wrong--or the definition I read last time was wrong. It's basically when a person has an unusually strong and--probably--sexual attachment to their sister. Which I guess is sorta the same thing I said above? Let me stop before I confuse myself. Ahaha.