Ryugu Rena is a manipulative serial killer, Age 13, she lures her victims by acting sweet at first, but then once she gets her chance, your no more than dead as she's quick to act once she senses or sees an opportunity to kill her prey. Once she's in her killer sense of mind, she finds anything that's laying around to use against her target, and to attempt to neutralize them. Once in her psychopathic raging killer state, she is hard to calm down, until she sees you die. 