Ryongul

[Mature Content]

[NO NTR]

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!

~~~~~
The MC will not start as a villain, but something will shift his mind in the future.

All-in-One System: All I Need is Erotic Coins

The scream coming from the training room did not sound like Hymot was in pain or anything like that, but Damian still hurried, opening the door as quickly as possible.

"What happened?" he said, staring at Hymot, who was sitting on the ground.

"You need to absorb me. This is the only way for me to survive!"

Damian was clueless about that and couldn't understand what absorbing her meant. Would it kill Hymot?

"This crystal allows me to reborn, but I need to merge my spirit with someone, and I choose you! I will lose all of my strength, so please don't abandon me!"

"I will never do that. So what do we need to do to merge?"

The moment Damian asked, Hymot's cheeks were red, and she couldn't say the words, only after gathering enough courage, "We… we need to have sex."

That was not what Damian was expecting, and even he, who was a man with experience in that regard, did not know how to react.

[Bonus chapter] Fucking a Dragon (R-18)