Mari has concerns for her classmate, Saegusa. Saegusa has been hanging out with a boy named Tatsuya, and she wants to make sure Saegusa is dandy. She invited herself over one day, only to be welcomed by Saegusa dressed as a cat and sucking on Tatsuya's dick like it's the most delicious thing in the whole wide world. How will Mari's sensitive sense of smell react to this?