MTL - Chasing Summer - Chapter 54

On earth, Felix is just a normal guy, a bit of a loner but otherwise normal. In the multiverse, under the rule of The System, he's a caster. Fascinated by magic and hungry to learn, grow and discover, this series follows Felix on his adventures through the integration and beyond.

After traveling for three years, Lin Yu was drawn into a horror game unexpectedly.

However, he discovered one thing.

The dungeon boss feared by countless players turned out to be the little loli who called her big brother next door.

then.

In the horror hospital, the director of the hospital turned out to be the uncle downstairs who made him and his granddaughter fall in love.

In the bloody slaughterhouse, the existence known as the bloody butcher turned out to be the uncle upstairs who wanted him to be his brother-in-law.

In Changteng Ghost School, the woman who frightens countless students is actually the long-legged sister Yu who invites her to her house for dinner whenever she has nothing to do.

…

Traveling through three years, you told me that this place is actually a horror game world?

(Introduction is weak, please read the text)

- Description from novelbuddy

The formless ancient world was infested with despicable demons. They hunted and feasted on mankind, keeping the human civilization constantly in a weak and suppressed state.

During the first known year, a magical mountain descended into the world from the realm of the Gods. Carved on this enormous mountain was a message: ‘Heaven Prevails’…

After the Grand Descent, a name that was given to the descending of the mountain, the Three Great Sages made their ways to Mystic Mountain where they learned to harvest what we now call magic, establishing the Mystic Cults and eighty-one sacred shrines to help aid mankind with the cult’s mystic powers against the eternal fight to the death with demons.

- Description from Novelupdates

A broken man who ended his own life finds himself reincarnated into the game he used to play. However, instead of becoming the protagonist or a powerful antagonist, fate places him in the role of a minor villain—a mere stepping stone for the protagonist in the game's first arc.