Can you have a crush when you're in a relationship?

Is it alrite to have a crush on someone even though you have a boyfriend?

In a relationshi,as long as your completely dedicated to your significant other,than looking at ther guys is okay.
However if you let it get to you,and constantly think about this other kid,and let it affect your relationship,then there is a problem.
If ever you feel that you are doubting the relationship,the you need to express that with your signicant other,because a one-sided relationship hurts.
I've bee in my current relationship for over 3 years.There have been many boys that've caught my eye,bu thats called lust.I've made lots of mistakes leaving my boyfriend for lust.It's not worth leaving your boyfriend for unless theres truly somehting better on the other side.

I agree with MrsCobain...
Its okay to look. But there is such thing as emotionally cheating on someone. Some people literally have an emotional affair on their significant other. Its a sad thing.

Heck no its not ok I go by this:don't do anything that you wouldn't want your boyfriend 2 do.