Kanda Sorata is a second year high school art student who was recently kicked out of the school's dorm because he was found keeping a cat in his room. Sorata begins to live in the apartment house "Sakurasou", infamous for its eccentric residents. Here, Sorata is asked to take care of one of his classmates, Shiina Mashiro. Although she is a brilliant, world-class painter, she is extremely clumsy and lacking in common sense. And thus begins the story of the master and his pet.