He Was My Brother Vol 1

From the Yen Press edition

In the high heat of summer, Kanoko visits her brother’s grave. By her side is Hijiri, her brother’s lover—and the man she has fallen in love with. But memories aren’t the only things that can haunt the living. This is the story of the twisted love between a girl, her brother’s partner, and the thing that was once her brother…

Source: Yen Press