A woman is whipped topless; however, she is wearing pasties, you do not actually see the pasties. (don't see the nipples?)

In one scene, a woman walks in on a man and another woman lightly petting (they stop when they see her)

Some of the costumes are slightly revealing.

In a deleted scene called "In All My Dreams I Drown", a character pins another character to the bed. This song also has suggestive lyrics.

A character gets his ear bitten and torn off his head.

A woman is whipped

In the song "A Penny for a Tale" a man sings about a greedy dog whose greed eventually leads the dog to drowning (not bad, but some might get upset with the thought of a dog drowning)

A girl is stabbed while spinning on a wheel

A man commits suicide by slitting his wrists, we do not see the actual suicide, but we do see some blood.

It is implied a man's son has died (again, not seen, but it could upset some people)

In the song "666", it is implied that breaking the rules might lead to 'bloody consequences'.

The f-word is used once.

A man smokes cigarettes.

compared to "Repo! The Genetic Opera" this movie is extremely tame.

some people (most likely younger children) might be a little scared by the appearance of the 'carnies', Lucifer in particular.

some people might get upset at some parts (like when it is implied the dog drowns and when we learn a man's son has died)

The entire tone of the film is dark, as these people have been taken by Satan and are being teased by Satan's carnies.