Rui is a very calm and quiet individual. He rarely raises his voice when talking to anyone. He loves playing Cat's cradle, a game where you create various figures with string using your fingers. He got famous overnight because he won the Cat's cradle tournament. He isolates himself from people. He likes to crochet. He likes reading about bugs, specifically about spiders. He has a pet spider at home. He also reads about crocheting. He is class Momiji.