Eraser

Talk about being a
pencil neck

Batman has one of the biggest rogue's gallery of any superhero. As such, he is no stranger to villains with weird gimmicks. The Eraser is definitely one of them.
History
Leonard "Lenny" Fiasco was a college student and classmate of Bruce Wayne. Lenny was constantly mocked by his classmates for his mistakes. Leonard had a crush on his classmate Celia Smith. However when he was about to ask her to an ice carnival, she decided to go with Bruce Wayne. Angered, this led him to a life of crime. Leonard became a cleaner (a criminal that removes evidence from crime scenes) that charged 20% of the crime's profits for his services. He donned a pencil costume and dubbed himself "the Eraser". Baffled by the Eraser, the police has Batman faked a crime scene and "hire" the Eraser to remove the "evidence". When Batman confronted him, the Eraser (due to various minor details) figured out Batman is Bruce Wayne and explained his back story. Batman revealed he doesn't even remember Celia Smith. Enraged, Eraser used sleeping gas to knock Batman. He dragged Batman to a recreation of the ice carnival. Robin freed Batman and the duo defeat the Eraser. The Eraser has since appeared mainly in cameos most notably "Batman: RIP"  (in Bruce's imagination) and "Whatever Happened to the Caped Crusader?".
Powers and Abilities
Like many Batman villains, the Eraser has no powers. However, he has gadgets instead. He wears pencil-point bladed shoes that can emit sleeping gas. He wears a helmet that has an eraser that he can use to erase things like fingerprints, footprints and so on.
References:
http://www.comicvine.com/eraser/4005-38566/