A Sister's All You Need., Vol. 2 (light novel)

Sister-obsessed author Itsuki Hashima is embroiled in a bitter struggle with his popular series Sisterly Combat. Between video games and mixed baths and cherry blossom viewing and making up excuses for his editor, he's slowly but surely making progress on his manuscript. Somehow, he and his unique collection of friends--Nayuta Kani, Puriketsu, Miyako Shirokawa, and his little brother Chihiro--manage to stumble through life together.

And not only that, but his friend Haruto's series has finally gotten an anime!