Reporter Clark is introduced to serial killer Alex through psychiatrist/Clark's ex, Oliver. Alex murders people he's involved with in order to preserve their love for him and Clark is an arrogant sociopath that gets off on manipulating others. Alex's behavior becomes unpredictable as his love for Clark intensifies and Clark leans on his friend/accomplice, the bribe-loving Chief Inspector (my favorite character) as he realizes he's bitten off more than he could chew with Alex. Eventually a stranger and Oliver are killed and Clark is kidnapped by Alex. Clark kills Alex, burns all evidence, then kills himself (and the fish Oliver gave him long ago) while holding Oliver's finger and his interview notebook on Alex. Solid story and characters, great art and pacing. A psychological horror with subtle yaoi.
Interview with a Murderer