>>2693343Any time the nudity is long-term.
A brief panty flash does nothing for me, but if the girl is forced to stay naked for hours/days/months then it becomes much hotter. When the situation becomes one of "Don't bother covering up, everybody is going to see everything anyways." that's when boner is achieved.
This can be anything from a lost bet "Spend a month naked if I lose? Like I'd ever lose, you're on!"
To a strange new rule "Sorry, we only issue one uniform per student. You'll just have to attend class like that until the winter uniforms are issued."
To even magical reasoning "The god has granted you powerful martial strength so long as you take a vow of extreme poverty. Yes, wearing clothes counts as owning something."
