From MangaHelpers:
Minami Eita lives with his older, book-loving brother, whose long-time girlfriend Arumi is often around the house. Minami tries to get along with Arumi, but the truth is that he likes her much more than is appropriate. Even though Minami doesn't read much, he helps in the library with his bookworm classmate Shinonome Yuuko, who loves short stories. She…