Monster Apocalypse: The Unhinged Beauty Is Forcing Her Love on Me!

[Apocalypse + alien species + superpowers + bodily mutation + two male leads + ABO + two powerful leads + reborn + pocket dimension + System + decisive violence + free looting + slice-of-life leanings + mutual salvation + unique independent world setting + feel-good protagonist POV]

Reborn after twenty years of apocalypse, he starts a life of looting for free with a spirit artifact by his side. When he runs into his scumbag ex and the woman who betrayed him, he beats them without hesitation. Just as he's about to kill them, he's told he has to transmigrate. Well, fine.

In a world three thousand years in the future, alien species have invaded. Earth's surface area has expanded without limit, technology has advanced, food and water are scarce, and humans are turning into beast-like alien species. Here, the strong rule!

His smooth-sailing monster-hunting adventure begins. After more than a year spent roaming a region teeming with alien species, he meets a cool, stunning beauty.

Might as well head into the city and take a look. When he registers, he's inexplicably paired with a male alpha beastman. Well, well, it's that handsome man! And now, for some reason, he's being asked to dissolve their bond?

What, you've fallen for me again? Sure, I guess! But you'd better watch yourself!

Scheming, lovesick bottom × unhinged, extremely jealous top

[Note: Don't skim or skip chapters. If something doesn't make sense, check the author's notes; explanations come later. If you still can't make sense of it, you probably skipped chapters, because missing even a single line can make later parts hard to follow.]