Apocalyptic Wasteland: My Romance System Built Me a Harem

GoodShort synopsis

In a post-apocalyptic wasteland, mercenary Ethan awakens the weakest Love System ever. But the target bound to his system turns out to be Emily, an SSS-rank high-level mutant. A handshake earns him fresh meat. A first kiss grants him a vaccine. And a bond unlocks a genetic evolution serum… While others can only strengthen one ability at a time, Ethan can unlock every resource by taming a beautiful mutant. As her Affection Level skyrockets, the once-feral beast slowly bows to him. But her gaze grows increasingly dangerous—and increasingly passionate. With the Love System, Ethan rises from a wasteland mercenary to become the ultimate King of the Apocalypse.