My Three Wives Are Beautiful Vampires - Chapter 682 : Pandemonium.

In short, MC inadvertently created a world, but as the creator of the world, he did not know the world at all. He should have lived here like a fish in the sea with some plug-ins that MCs always have. But now he is even stumped by the bugs in the instant world. Luckily, in this world he has found his shadow guard, or his lover? So the daily adventure is getting not so boring…

- Description from Novelupdates

Sato Yu is a 12-year-old boy. He is a deprived person. His life is depriving. His step father has a large amount of debt.

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.)

The heavens and earth change when the blood phoenix descends.