Ryuusei plays the role of Kibayashi Nagumo, an employee of Forest Funeral Parlour who visits UDI often for work to deliver corpses for investigation. He also has an ambiguous and mysterious relationship with Nakadou which offers a lot of room for imagination. Ryuusei commented that there is still a lot which he doesn't know about Kibayashi based on the scripts he has received so far so he will have to build up his character bit by bit on a trial and error basis. Nonetheless, he is eager to find out how Kibayashi will interact with the UDI members and how his presence will affect the story so he called upon viewers to check this out when the drama airs.
Sources: Nikkansports / Oricon