Selfish in bed

I feel a bit bad about this..

But lately I've been fantasizing during sex about having a threesome..

With my husband and a (fantasy) girl.. And it turns me on bad.

I think mostly because I really love my boyfriend in a way that I'm not even attracted to any other guys.. Is probably why in my fantasy it's a girl.. Because, though I feel girls are in general prettier than men, I've never actually been attracted to any female.

Why I'm feeling bad about it.. Is mostly because I want all attention turned to me.. It feels selfish.. And that feels kinda wrong to me.

Honestly.. I'm sure I don't want anyone else there.. But I think it's just the imagination.. The fantasy.. That turns me on...