Ore no Shita de Agake
俺の下であがけ
Manga based on the BL game developed by Alice Blue. Each storyline has a different author:
Prologue: Akira Norikazu
Kurosaki x Higuchi: Reno Amagi
Kurosaki x Shimizu: Reibun Ike
Kurosaki x Yamaguchi: Ryou Sakura
Kurosaki x Yoshioka: Wren Tamaquis (Source: M-U)