Pedophilia

Pedophilia is a psychiatric disorder in which an adult or older adolescent experiences a primary or exclusive sexual attraction to prepubescent children. Although girls typically begin the process of puberty at age 10 or 11, and boys at age 11 or 12, criteria for pedophilia extend the cut-off point for prepubescence to age 13. A person must be at least 16 years old to be diagnosed with the disorder, but late adolescents must be at least 5 years older than the prepubescent child for the attraction to be diagnosed as pedophilia.

Pedophilia has been referenced numerous times in South Park and has also been the subject of many episodes, and been shown whenever the act of child sexual abuse is committed.

Background
In "Cat Orgy" it is revealed that 12-year-old Shelly Marsh has an adult boyfriend who is part of the band The Lords of the Underworld.

Pedophilia becomes a core plot point of "Cartman Joins NAMBLA", in which Eric Cartman abandons his friends in pursuit of more adult-like ones, only for this to turn out to be a big mistake as he is targeted by the NAMBLA. Mr. Garrison also tries to solicit sex from Cartman earlier in the episode, which lands him in prison and becomes a plot element throughout Season Four.

All of the South Park kids accuse their parents of sexually abusing them in "The Wacky Molestation Adventure" to get them arrested and have no authority in their way, having the whole town to themselves.

In "Miss Teacher Bangs a Boy", Ms. Stevenson engages in sexual activity with Ike Broflovski, which is definitely pedophilia or infantophilia.

Pedophilia becomes a plot point once again in "The Return of Chef", in which Chef is brainwashed by the Super Adventure Club into becoming a pedophile and making sexual advances to the Boys, who notice that Chef is not acting like his normal self.