How strong the reluctance to risk losing social value is.
You would expect that perhaps a girl would not want to kiss a guy
acting weird that she doesn't know.
But what's interesting in this video, is that also guys refuse to kiss a
beautiful girl, when she is acting in a way that is `weird', like she is one of the outcasts
they do not want to associate with (see e.g. 2:25 below)

http://www.youtube.com/watch?annotation_id=annotation_65850&feature=iv&src_vid=YvupkMJWAaM&v=YkZav1m9oSI