Skip (real name: Steven Westcott) is a minor villain from Marvel Comics. Skip most notably appeared as a flashback antagonist in Spider-Man and Power Pack #1, an early era Spider-Man comic, in was what is known as a "special issue" character and thus was designed to warn children about real-world dangers (in this case child molestation).
He was created by Nancy Allen, Jim Salicrup and the late Jim Mooney.
When Peter Parker was younger, he first met Skip during a visit to the public library. Peter's studiousness impressed Skip, nicknaming him "Einstein", and the two became fast friends, something encouraged by Aunt May, as she had been worried that her nephew spent too much time alone and didn't have many friends. Peter and Skip would often spent time alone at the latter's house while his mother was away at work, and one night, Skip showed Peter some pornography, and suggested that they "touch each other like the people in the magazine." Peter was terrified by this, but, according to him, was "too frightened to leave", implying that Skip had molested him in some way. Peter then stopped spending time with Skip and eventually worked up the courage to tell Aunt May and Uncle Ben of what had happened that day.
It's never stated what happened with Skip after this, but it's highly likely that Skip certainly ended up getting arrested for his crimes as Aunt May and Uncle Ben would have surely informed the authorities of the incident as they were extremely protective of Peter as well as of strong ethical backbone, although another possibility could be that Skip got severely grounded by his mother. Either way, it's made clear that Peter never saw Skip again afterwards.
Years later, Peter overheard his young neighbor Tony Lewis rejecting the advances of his baby sitter Judy, who wanted him to strip himself from his clothes. After changing into his Spider-Man persona and scaring Judy away, learning of how she had been touching Tony in the wrong ways, Peter (without naming himself) told the young boy the story of how Skip had sexually abused him as a young child. Peter then swings Tony across town to his parents and returns to his apartment, satisfied in helping his neighbor and confronting one of his own personal demons.
Spider-Man later recalls these events again during a fight with the Hobgoblin.
It's unknown if Peter was Skip's only victim, though it is unlikely as Skip had the personality of a sexual predator - meaning he likely abused others.
Jim Salicrup, one of the writers who wrote the comic, has stated in recent years that he profoundly regrets having written the comic book and created Skip as many comic book fans have bothered him about it on his Twitter account, making Skip one of the most hated and infamous Spider-Man villains in spite of being a normal human with no powers.
Like many older era comics, it is unknown if this event is part of current Spider-Man canon or not. Furthermore, it's speculated that these events perhaps never actually happened and that the story was made up by Spidey himself to teach Tony a lesson, but there are no ways to prove that.