Jujutsu Kaisen: I Can Travel Back in Time - Chapter 25 - 19 Oops! I forgot about the curtains!

It started off peculiarly; first, his domestic cat refused to let him cuddle it.

Lin Qiushi soon found that a sense of disharmony and incongruity began to pervade everything around him.

Then, one odd day, he pushed open a door, and he discovered that the hallway he was familiar with turned into a boundless corridor.

At both ends of this corridor were twelve, identical iron gates.

Thus, the story began.

Ruan Nanzhu said to Lin Qiushi, “When you gaze into the abyss, the abyss also gazes back at you.”

Upon hearing this, Lin Qiushi sank into deep contemplation. He then pulled down the zipper of his trousers and aimed at the abyss…

Ruan Nanzhu: “…Put your pants on properly!”

Super shameless, ill, pampered gong X Shameless, calm shou; a combination of double [or extreme] shamelessness.

- Description from Novelupdates

In the celestial empire, during the ninth year of the Mandate of Heaven,Chaos reigns across the land, and the people suffer.The royal governance collapses, and western barbarians with their pantheon of gods invade.New warlords arise, claiming territories; the Taiping rebels wreak havoc, leading to widespread misery.Calamities like floods, droughts, earthquakes, sandstorms, tornadoes, acid rain, blood moons, and meteor falls occur in succession.Countless demons roam, strange beings thrive, spirits mingle with the inexplicable, and mysterious phenomena arise.In these dark and tumultuous times, Tao Qian opens his eyes to find himself about to be beheaded at the vegetable market...

800 years ago, 3000 dimensional gates opened across the entire world. In that moment, it was as if 3000 different colored eyes opened across the world as hordes of monsters swarmed out of these gates like tears.

Some could destroy city walls with one strike; They had bodies the size of a giant and fed on humans

Some latched onto humans, absorbing their bodies’ nutrients and enslaving humans

Some infiltrated the humans’ cities, disguising themselves as normal human beings while feeding upon human blood to sustain themselves.

In a night, the Human race fell to the bottom of the food chain.

The world had turned into a paradise for monsters…

- Description from Novelupdates

The main character is reborn as a character from a game he played in his previous life. This character falls into ruin along with the villainess, spending the last of their years together. A man named Kururi Helan.