Why? Well a couple of weeks ago I gave him some old comics I used to own. One of them was Legends of Dark Knight #49 from DC Comics. Published in the early 1990's where the Catman starts "hunting" young women. Batman and Catwoman form an uneasy alliance to stop him. The story features an alternate origin and characterization of Thomas Blake. Batman wants to apprehend him, while Catwoman wants him dead. They eventually catch him and, between the two of them, beat him to a bloody pulp, although Batman is able to restrain Catwoman from committing murder.
The comic is bloody and violent but my son simply can't put it down and "read it" almost everytime he's in my car. No need to tell you that we went crazy when I discovered both Batman & Catwoman at the flea market.