Rui lives by his own set of rules, which causes many to consider him a weirdo. He is almost always smiling and sometimes gets carried away by his ideas. Despite the apparent riskiness of his ideas, Rui does his best to take safety into consideration. He's extremely intelligent, often working on and making robots and toys. He has yellow eyes with red eyeliner along the crease, and uneven, choppy purple hair with two cyan streaks. Rui does care deeply for his friends. He's also quite a tease.