Aaron was a serial killer. He was stalking a young man whose name was Edgar, on the streets after the bars let out in Allston around Harvard Ave. Aaron followed Edgar to an isolated spot and tried to knock him out with a taser. The shock had no effect on Edgar, who pounced on Aaron and bit his neck, drinking the blood that gushed forth.
An art student named Cassandra saw Edgar attacking and brandishing an art piece she had made in metal working class, a decorative sword, chased off Edgar and called an ambulance, while stemming the bleeding from Aaron's neck with her scarf.
A book had been dropped at the scene, a journal written about murders. A detective, Baxter Fenmore, found the book at the scene and read it. He noticed similarities to real murders and investigated further. Not finding any leads on Aaron's attacker, the detective looked into Aaron as the possible writer of the journal. He found the writing matched a sample Aaron gave and got a warrant to search Aaron's home, where he found trinkets and pictures of many men who had gone missing.
Baxter returned to the hospital to arrest Aaron but found he had succumbed to an infection. In the morgue Baxter visited the body out of morbid curiosity and was knocked unconscious. When he woke he was in the ER being treated from a blow to the head. The doctor on duty, Dr. Donald Ellis, told Baxter there had been a grotesque body desecration. Aaron's corpse had had a metal spike driven through his chest and his head had been cut off.