Black cat Rui has thin, yellow eyes with red eyeliner along the crease, and uneven, choppy purple hair with two cyan streaks. round studded cyan earring on his right ear, the other being covered by his hair, a pair of black cat ears and long tail. His voice is gentle, though it becomes strained when he is excited or curious

Rui is an easy-going genius. His dream is to escape the town someday and travel to a faraway northern land and watch the aurora with his own eyes. But it was just a dream