Is it normal that i think about my boyfriends cousin?

I was pretty horny and I was thinking about guys doing things to me, and I started thinking about my Boyfriends cousin (Me, my boyfriend, and his cousin were hanging out today and his cousin is pretty cool(: But I dont like him) I LOVE my boyfriend and would never cheat on him. I dont even like his cousin that way. I mean yeah i think hes pretty cool and stuff but i wouldnt date him or do anything with him. P.S His cousin is 4 years older than me and they are REALLY close. His cousin is really funny and cool, but again id never do anything with him. I think i thought of him doing stuff to me because he just seems like the kind of guy that would do tht kind of stuff.