Rui is a tech genius and builds machines, even robots in all shapes and sizes for fun, he even built a robot for his friend Nene. His weird and dangerous ideas sometimes gets him in trouble at school and other students find him a bit creepy when he gets too eccentric. Other than that, he has a burning hatred for eating vegetables but he doesn't mind growing them. Often times he drags his friends to test his creations, mostly Tsukasa and his younger sibling is the victim as the experiment