Isekai Maou to Shoukan Shoujo no Dorei Majutsu - Volume 10 Chapter 3 part8-9

Read at least six chapters, then prepare to crave the rest.The main character will show up in Chapter Five, though I don't recommend skipping the first four chapters.-----The world was celebrating. The Demon King was dead, along with his Darkness Generals.Humans led the other races to war for subjugation. They killed all, and none were spared. However, thousands of years before this happened, a piece of history was altered by time itself. In fact, the Demon King didn't have four generals but only one, which he sealed and sent into eternal slumber. Just as he started to close his eyes, the chains locked away for eternity shattered into pieces.

He was the CEO of the Mu’s Group. He had a respectable status and a domineering attitude. His biggest weakness was that he doted on his daughter. For his precious daughter, he came to her and signed a contract for her to be his daughter’s nanny. She thought it would be fine to stick to the contract, but he interfered more and more with her, driving away every man around her without leaving a trace, locking her in his arms, saying to her affectionately and tyrannically, “We should give a companion to our daughter.”

Rokuhara Souta picked up a phone with a mysterious “Friendship System” installed. On that phone, he met an online friend with the nickname “Tokisaki Kurumi.”This online friend was a total roleplay enthusiast—her portrayal of Kurumi was so convincing it was almost eerie.Finding it amusing, Souta humored this hardcore chūnibyō (delusional teenager) and casually chatted with her.Since it was all fake anyway, he spoke without restraint, often throwing out flirtatious remarks just for fun.Until one day, he received an invitation from Tokisaki Kurumi to meet in person.And then… he transmigrated!In a filthy, bloodstained alley, dismembered human limbs lay strewn in the corners, the pungent stench of blood stinging his nose.Standing before Souta was Tokisaki Kurumi, fresh from a kill, smiling sweetly as she gazed at him…(Tentatively planned heroines include Kurumi, Oshino Shinobu, Military Princess(Re:Creator), Kamado Nezuko, Ereshkigal, Leticia… and more.)

He holds a god-level sign-in system in his hand, punches the goose factory, and steps on the pig factory. Do you think there is no good game?
First feed you two mouthfuls of tainted milk powder, and then send you the legend of the dragon and the Hearthstone gold cartoon for free.
What? Still not satisfied? League of Kings out-of-print skin, give away!
Satisfied? Tch, this is just the beginning…

- Description from novelbuddy