i don't see the problem with just getting it out of the way. just because you don't lose your virginity to someone special doesn't mean it's going to be ruined when you do meet someone special.
maleficent, in a way you'd be doing him a big favor because i'm sure you have a lot you could teach him. however, if the friendship is truely as one-sided as you say, then perhaps he thinks
you are someone special and is just using the "just to get it out of the way" line so you're more likely to say yes.
but as you said, you pretty much already know what your decision will be, so good luck or have fun... whatever the case may be.