Invincible Starting from Max Level Attributes - Chapter 874 - 900 What kind of bizarre setting is this?

Transmigrated into the world of High School DxD, Roy believed he had been handed a life of luxury and glory. Born into the prestigious Lucifuge family, with his Sister Grayfia as his strict yet devoted older sister, he thought he was destined for greatness. 99,997… 99,998… 99,999… 100,000!!But... reality proved harsher: Roy lacked demonic talent and, despite years of training, remained a Low-Class Devil. his peers effortlessly achieve High-Class status, he’s been trapped in a cycle of endless sword practice and ridicule. Yet, he refused to accept mediocrity. Ten thousand sword swings a day, relentless training.. Until one day..[Ding! The Strongest Demon King System has been activated. Access functions to learn more.]---- High School DxD - Main World!1 - High School of the Dead [●] - First2 - Demon Slayer [●] - Second3 - Akame Ga Kill [●] - Third4 - Bladedance of Elementalers [●] - Fourth5 - Campione [●] - Fifth

You Liangxing would never open the speech function in game.
That was because his voice was…
Particularly! Kittenish!

But there was one day, he queued up with a teammate who had so much to say that they may as well explode. Vexed to the point of no return, he contributed a voice that was capable of splitting heaven and earth, “Don’t BB.”
The other party who was being scolded stilled. In the ensuing silence, he suddenly let out a long, relishing… Moan.
You Liangxing: “…..”

Later —
He realised that the person was a great god,
Much later,
Without him realising,
He became the great god’s royal healer.
…. And also his boyfriend.

- Description from Novelupdates

There are countless parallel worlds beyond what we know. The people who first discovered this secret named it “Yan Fu”. Each world is a different fruit on a tree, and the person who shuttles through different fruits is called “Yanfu Walker”. Yanfu Walker is given different Heritage and trained to complete Yan Fu missions in exchange for rewards.In modern society, the Martial Arts sects have declined one after another, and martial arts prodigy Li Yan suffers from leukemia, making it difficult to survive by opening an audio and video store. One day, a person named MO appeared and took him into the Yan Fu world under the pretext of being able to cure a terminal illness. So “Hejian Skinny Tiger” Li Yan resolutely stepped into the world of Yan Fu, awakened the inheritance of Gu Huo Bird, and embarked on the path of survival in a different world. The truth of the world, Yan Fu’s goals, the secrets of the walking organization, and the ambitions of the rebel organization are far more than that…