SADIES NIGHT: i want to kiss her but......?

ok so after the sadies dance, me (im a guy) and some other friends are going over to my friends house until probably 2 or 3 a.m. me and my best friend are gona be the only guys there and there are gona be about 6 girls. we will probably watch a movie or something. i was wondering if during the movie, if she is sitting next to me and then she like starts to lean against me and lay her head on my chest, do you think that is a sign that she might like me or want to kiss. so if you were that girl in this situation, do you think u would want that guy to kiss you. if i do try to kiss her, whats the best way to take her aside to a more private place cuz we are gona be with all our friends.