Y'know, It's possible. It entirely depends on the person. If you spend enough time thinking about this character and wanting to have sex with her, I imagine that eventually, you may in fact dream about having sex with her. Then again, your brain might just say "**** you" and not actually dream about what you want it to dream about. Dreams seem pretty fickle to me. Can never tell what the subconscious is gonna decide to show me, if anything. Anyhoo...

Wuv, Yer Mom