Some kissing.

A mature sexual situation is portrayed in this movie. But the way it's shown in the movie it's more goofy and funny than actually mature. Nothing sexual content or nudity, but there is quite a lot of dialogue referring to sex: A man tells his wife he remembers the exact date they stopped having sex. There are other mild/moderate references like that, but there is rather a strong one where a woman explains to her brother that she was tied to a bed and defecated on. This is referenced later when the brother says to his wife "A strange man defecated on my sister."

One G-ddamn.

One or two uses of 'bullshit' is the worst it gets.

Drinking games are seen performed by kids not of the legal age to drink. Other than that there are a few parties at which adults drink. Mild smoking and a few drug references.