Tatsumi Koutarou is the self proclaimed mysterious manager of the idol group Franchouchou in Zombie Land Saga.
He has brown hair, always wears sunglasses even during the night time, and also wears his jacket hanging on his shoulders and dried squid hanging off of the breast pocket of his red vest. His appearance is more or less likely based off of his voice actor, Miyano Mamoru, who has made several appearances in-character within promotion.
While he generally treats the girls with a jerk-like attitude, it is made clear throughout that he does indeed care for the girls; particularly Sakura. In Episode 12, it is revealed that his real name is Inui, with strong implications that he had a crush on Sakura who was his classmate prior to her death in 2008.