Imouto sae Ireba Ii.  

A Sister's All You Need, It'd be Good if Only Little Sister Was Here, 妹さえいればいい。

Hopeless siscon Hashima Itsuki has a diverse group of friends who each have their own struggles. The first class genius and lover, Kani Nayuta, is troubled about love and friendships. Shirakawa Miyako, the victor of three crowns, battles with her emotions even in her dreams. Oono Ashley, the brutal tax sabre, grapples with his past mistakes. Puriketsu, a natural-born illustrator, struggles to balance his artistic talents with his personal life. Despite their individual challenges, they all share a passion for playing games together, taking trips together, and working together. Watching over them is Chihiro, the kind and thoughtful little brother of Itsuki, who harbors a secret of his own.

Imouto sae Ireba Ii. has been licensed in English as A Sisters All You Need by Yen Press.