Maybe a Fake Gintama - Chapter 53: Keep Quiet in Public! Don’t Cause Trouble to Others! (Sakamoto Tatsuma Appears!)

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

The day dungeons appeared on Earth, everything changed! From ordinary beasts to monstrous ones, attacks were common throughout the globe, and no one was safe.

After countless studies using these beasts as subjects, Humankind developed a serum capable of awakening incredible abilities in humans, leveling the battlefield.

With the serum came heroes and villains, those who wished to use their powers for good or bad.

The Garmony Upper School was a place for the elite with the sole purpose of creating heroes to fight the villains and explore more of the dungeons after the beast attacks increased for no apparent reason.

Damian Romero, a youth who received the serum after turning 18, yet got no unique ability. It was not uncommon for one to not receive power, but it was still a blow to one's pride.

He went rogue after the news, drinking alcohol and having a good time with women, and it was at that moment, when he was putting his toy to play, he got a surprise.

[All-in-One System Unlocked]

Damian's unique ability was a system with multiple functionalities, but after he studied it, it seemed this system worked with a different type of coin called Erotic Coins!

Improve his body? Buy any item or unique ability from his system's store? All Damian needed was Erotic Coins, and he knew how to earn them!

I’m in a secret, bad romance with a love dependent student—「Having a secret meeting with a student one is in charge of at school… Isn’t it exciting?」The special relationship with Kirihara that no one can know about began when I took up my post at Mori Kawara High School as a teacher.At school, she’s the serious student council president who has earned a lot of trust from other teachers, but when it’s just the two of us, she becomes mischievous, clingy, and jealous.On weekends, I cook meals at her place, play games together, and pamper her as if we were lovers.Unable to reject her because she knows my weakness, and despite knowing it’s wrong, we continue to pile up secrets little by little every day…「Sensei, my feelings of liking you have grown very strong.」As Kirihara openly confronts me with her feelings, the emotions I’ve been holding back grow even stronger.Even though it would all be over if it were exposed, that sense of immorality ironically only accelerates things further—

In the era of Beast Taming, Ye Xuan with his superior Beast Editor, claims that he can turn even a snake into a Divine Dragon that soars across the nine heavens.