MTL - Pierce Heaven Til’ It Breaks - Chapter 3 Jiao Jiao's mind

Liam feels increasingly suffocated by debt, paralyzing shyness, and the monotony of everyday life. However, everything falls apart when he is falsely accused of a crime and is on the verge of being expelled from university. But as he's wandering hopelessly back home, a strange voice echoes in his head, informing him that he has received the “Harem App.”Suddenly, his life is turned upside down, and he now has supernatural powers to win over beautiful women. At the same time, he finds himself entangled in conflicts far beyond those of a mere human.

Being given a chance and reincarnated is nice and all, yet why do I have to become that male friend who just watches the protagonist flirting with his harem?---World: Kaguya-sama: Love Is War - Hyouka ----

Ruel finds himself thrust into a brutal post-apocalyptic world, bound to a bizarre “Milf System.” This system demands morally questionable acts – NTR, seducing milfs, and claiming other men's wives – as the sole means of gaining strength and essential survival skills.The brutal reality of this new world awakens Ruel's hidden lust and dark desires. He swiftly abandons any semblance of morality, embracing the system's perverse demands with growing fervor.Driven by an insatiable hunger for power and pleasure, Ruel revels in the ravages he inflicts, using his newfound abilities to dominate and conquer.His journey transforms him into a ruthless force, where survival is intertwined with the satisfaction of his darkest urges, leaving a trail of broken relationships and conquered women in his wake.

A back-to-basics(?) monster evolution novel.