Why do girls say ewww, when a guy does something sexy that turns them on?

ex. a week ago I was at a party and went streaking and this girl saw me and stopped to check me out, and has kinda been trying to get close to me lately, but while she was checking me out she was like ewwww ofc. and then a while ago I did a cam for this girl and her friend and at the time she was like, "why are you naked?" But then later when I saw her and her friend at school they both gave me lusty looks. Why do girls pretend to be disgusted, even when they like stuff?