I feel it is wrong, but still wonder if every one would worry so much if it was a 15 years old girl with a 21 year old guy, sort of reversed standards

Same Laws and responsibility of parents and caregiver apply Lion 

Most people here have been 21 (an adult) did you date or even think about dating a 15 year old (child ) ?

what on earth would a 21 year old have in common with a 15 year old

Lust?

I feel it is wrong, but still wonder if every one would worry so much if it was a 15 years old girl with a 21 year old guy, sort of reversed standards

A 15 girl with a adult male is wrong on many levels.

I suppose as adults we need to ask how we would feel and what we would do about it if either the 15 or 21 year old were our children (regardless of the gender.) We need to look at it as adults not as the 15 year old we once were.They require protection for a reason.

Though remembering back I was 17 when my brother was 15.Some of his friends had crushes on me but even then with me being only 2 years older they were to me too young,not mature enough in mind or body.

A 15 girl with a adult male is wrong on many levels.

The Law is the same regardless of gender.I have 3 sons.I would not allow a 21 year old male or female to abuse them....or get away with it if they did.The adult needs to behave like an adult or be accountable if they don't.

Same rules and Laws apply to my daughter.It's my duty to protect her.