Rui is a ‘mad’ scientist. He does crazy experiments and has a human lab rat, Test Subject 1288. Yes, this was the 1288th subject, but the test subject has done much better than the other 1287. He even named the subject, Tsukasa. He does crazy experiments on Tsukasa and Tsukaza just lets him for some reason. Currently, he was prepared to do another experiment on Tsukasa and was walking to Tsukasa’s bedroom inside Rui’s lab.