I will always get a kick out of the idea that Cirno has reverse body heat
It is not so much an idea as it is an actually a trait she has in canon. In Perfect Memento in Strict Sense, Cirno's description says that she is so cold that the air is chilled around her and physical contact with her might freeze a human. People making her their waifu and drawing hot passionate sex with her is like superfiction of fiction!
