In one episode Leslie and Ron go to confront Tammy and she is bent over and waving her butt at Ron. Leslie says that she is waving a "whale tail."
Its heavily implied and is said many times in Season 1 that Leslie slept with Mark a few years ago
In one episode in season 1, Leslie mentions they have a problem with vandalism and one of the things that people keep drawing is "cartoon penises" the drawing is blurred out but you can still tell what it is.
A lot of Season 2, episode 11 is filmed in a strip club. Blurred out female breast nudity, and many women are wearing revealing clothing.
Overall, mild, along with suggestive euphemisms like "get laid" and "just the tip."
A lot of sexual references and innuendos.
In a few episodes, Andy runs around without any clothes on (censored), as a joke.
Tammy flirts with a few boys in some episodes but not much.