
S01E01 The Special Circumstances of My Bathtub
High school student Tatsumi lives alone. One day he spots a person while walking by a river. He approaches the figure and discovers a beautiful man collapsed on the ground.
Wakasa is shocked when Tatsumi leans over the tub and announces it stinks. Tatsumi cleans the tub responsible for the odor and transfers Wakasa to a children's pool. Saying, "Brother, tell me if you're using the pool," Kasumi mistakes Wakasa for Tatsumi and hugs him.
Tatsumi is a high school student who lives on his own, until a merman named Wakasa takes up residence in his bathtub. His solitary lifestyle is turned upside down by the self-centered (but handsome) new roommate.