He's not imagining raping you
he's imagining you consenting and enjoying it. If you got a text saying "hi hun been thinking about raping u, got me hot, xx" or something, I'd see your point.

If he was enjoying daydreaming about going to the park with you for a lovely walk, would you object on the grounds that you don't like going to the park?
( Flapjack I spay a little mare for you, Mon 10 Dec 2007, 13:25, archived)

Hmm yeah
actually a good point. Although if he was imagining me doing something I really hated, however innocent, I'd kind of wonder why he was imagining me being like somebody else.
It's just the idea of being thought of as a sexual thing, to me, it's horrid.
( Moon Girl Technologies horrendous beanbag, Mon 10 Dec 2007, 13:30, archived)

I promise I'll do my best not to
but you can have sex without treating someone like an object, despite what internet links might have you believe.
( Flapjack I spay a little mare for you, Mon 10 Dec 2007, 13:35, archived)