Carnival in Brazil. What to expect?

My boyfriend has had a life long dream of going to Carnival coming up in February. I know no one on here knows our relationship, but we really trust each other. I would love to go to it also one day. But this was one of my to-do's before he and I met.He thinks he's going to go have a wild time and its just going to be so much energy he might have sex with whomever is in the moment with him. Does this really happen? I can imagine how wild and fun and powerful and exciting it is. But does this stuff happen? Like is it a wild flashy swingers party? Sorry to say it that way. But I want him to go, since its his dream. But I also don't really like knowing he's mixing body paint with some other person... What should he expect? Or me if I went?
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Geez, for those thinking he's going to hook up with a prostitute, that has nothing to do with it. He was talking about the energy of everyone dancing and having a good time. He isn't going to go for just sex, just for the energy of Carnival. He was thinking it was almost primal at times. Not a whore house. I guess I should have asked if people hook up a lot there or is it just a good party? I'd go with him, but he's wanted to do this before we met and I'm all about pursuing your dreams... just wanted to know what he can actually expect there.