Joukakei Kareshi by Satomaru Mami

Summary

Plot:Chapters 1-2: After being dumped by his cheating boyfriend and on the cusp of going into heat, Bandai is rescued by Nagaoka. For Nagaoka, it’s love at first sight. But the bitter and disillusioned Bandai decides to take advantage of Nagaoka’s kindness to get back at the world. Can these two find their happiness together?Chapters 3-6: Shichiku a beta, keeps losing out to other alphas around him and he takes out his anger by having sex with a sweet omega named Nagisa. 7. Extra Note: the title roughly translates to “Purifying Boyfriend.”