MTL - My Extraordinary Achievement - Chapter 75 Grandpa can only help you here.

An ordinary person who has passed through the Marvel World to gain the phagocyte ability and began to devour superpowers, and became the king of Marvel!

There are many female lords. The protagonist has gradually become the king of the Marvel world from ordinary people. The initial ability is the physique that changes through traversing. It can devour and stabilises without any side effects. The system is only an aid, you can also cross the plane!

- Description from Novelupdates

He once stained the rivers and mountains with blood, his brilliance unparalleled. Unexpectedly, he encountered a great calamity, a dragon trapped in shallow waters, everyone thought he was nothing more than a useless son-in-law. But how could Gold Scales belong to a mere pond? The returning king, under the name of Frenzied Son-in-Law, with the War God’s stature, swept across the Eight Desolations of the Four Realms, the world trembled beneath his feet!

Holo’s life was once a series of relentless hardships—bullies at school, abusive parents, and heartbreak at the hands of those he trusted. After a failed suicide attempt, a mysterious man offers him a deal: help rehabilitate four psychopathic girls, and in return, earn ten million dollars. Desperate and naive, Holo accepts, not realizing the chaos and danger awaiting him.Each girl comes with her own dark tendencies—Trixie, a violent and feral girl who acts on impulse; Scarlet, a master manipulator who delights in breaking people down; Felicia, a dangerously seductive woman battling a sex addiction; and Eleanor, a cold, calculating girl with a desire to watch the world burn. As Holo works to bring out their humanity, the girls become obsessively devoted to him, their love transforming into something darker.