The School Beauty's Personal Killer

If the killer isn't trying to show off, then what's the point of killing? The king of the underground world returned to the city because of a promise and became the personal expert of the school belle. He originally wanted to be a low-key pretty student, but he was constantly harassed by all kinds of beauties, including the school belle, lolita, royal sister, neighbor, and urban white-collar workers... School belle: "Brother, I'm afraid of the dark. Come to my room at night." Loli: "Uncle, you are so wretched." Sister Yu: "I won't close the door tonight..." Neighbor: "Don't peek at me taking a shower, pervert." Protagonist: "... Wait a minute, let's sleep together..." This novel and its characters are purely fictitious. Any similarity is purely coincidental and should not be imitated.