How would you handle this "spin the bottle" situation if it was your daughter?

I consider myself pretty liberal and relaxed about things in general, but this has been bugging me for days. My 12½ year old daughter was invited to a sleepover for one of the girls on her volleyball team. There were like 8 other kids there, all friends, so it sounded like a fun time for her. I met the parents, and they seemed like totally normal people.

Anyways, the next day my daughter was telling my wife about how the girls all started playing spin the bottle. My daughter said “I didn’t know all my friends were bisexual” and talked about how she was grossed out by some of the girls “kissing with the tongue.”

I remember what it was like to be in 7th grade, and I did a lot of the same crap. But it feels WAY different from the other side. I don’t want my daughter to not tell us what’s going on in her life, and I don’t want to call the parents and have her friends hate her.

Maybe I just have to accept this is the way it is, but it’s bugging me. I don’t really see how a bunch of 12 year olds could be in touch with their sexuality enough at that age for them to all feel they are bisexual. I blame Girls Gone Wild and shit like that.

Any advice?