I Didn't want to be the Karma Killer... (The Karma Killer Book 1) by Brandon Nathaniel Boodoosingh

Karma Leto is the son of two billionaires. He has always wanted to be a superhero, however, circumstances have forced him into being a serial killer. By day he's in high school, and by night he's killing criminals. He has to deal with his laughable love life, unstable friendships, not getting caught, making the bodies disappear, and his own mental health, all of which will unravel their true natures through the story. School will eventually end, but there's always evil in this world, so there's always something to cut up.