A few sketches feature characters drinking, most notably the whiskey one where Trevor's character attempts to re-enact Super Size Me but with alcohol instead of fast food.
S1E8 - A sketch involving a married couple attempt to roleplay a rape scenario, which goes wrong when the wife mistakes her husband for an actual rapist.
S2E5 - A sketch involving two children deciding to rape an attractive older babysitter (The sketch ends directly after the idea is presented, so no onscreen assault)
S3E4 - A sketch parodying Lord of the Rings ends with the fellowship raping Gandalf. The rape is not shown onscreen but rather a voiceover (a la the Lord of the Rings films) describes that raping Gandalf became a national pastime for years after the events of the sketch.
S3E14 - A sketch involving a commercial for grape juice features a character in a grape costume named "The Grapist" (similar to the Kool-Aid Man) who bursts through kids' bedroom walls screaming about "graping them in the mouth." The scene reveals to be a pitch meeting for the commercial, where the advertising agents are horrified at the language in the commercial, while the director of the ad maintains the commercial's innocence and accuses the ad agents of being perverts for making the connection.
S1E1 - The "Get a New Daddy" song aims to teach kids that if they don't like their father, they should take naked pictures of themselves and put them in the father's drawer. (The series is aimed at adults, and the satirical song is not actually aimed at children)
S2E5 - A sketch involving "irresponsible programming" shows a scene of a kid befriending a stranger in a van, who tempts the child with candy. The scene quickly cuts away to a "please stand by" card.
The "Get a New Daddy" song aims to teach kids that if they don't like their father, they should take naked pictures of themselves and put them in the father's drawer. (The series is aimed at adults, and the satirical song is not actually aimed at children)
If there's a female character in a sketch, there's a 90% chance that they will be portrayed by one of the boys cross dressing and putting on an exaggerated voice.
The x-ray glasses sketch implies such things, as does the cat food commercial sketch. The Mission Impossible sketch also has an offhand reference to oral sex with a dog.