Haikyuu: Zero To Almighty - Chapter 13: Aoba Johsai

Yu Sui and Shi Luo met each other when they were much younger. One was a pro-gamer, a widely-renowned, best of the best, in-game medic. The other was an e-sports newcomer who was just starting out. The two originally played for the same team, during which their relationship became increasingly deep.

He lived from BC to the Middle Ages, from the Renaissance to the Industrial Revolution, and from Cyberpunk to the Interstellar Age. He has been a king and a prophet, a knight and a nobleman, a versatile artist, a genius inventor…
This is a four-thousand-year human epic——
“To us four thousand years from now:
“Is the world at peace? Is famine extinct? Can people touch the stars? How long is the human lifespan? How far is the boundary of the earth? Human…do you remember us?”
——Excavated from Earth Age Tenth Century BC, Solomon Prayer Book.

- Description from novelbuddy

The ordinary yet not so ordinary detective, Wen Wen, woke up in a mental hospital and discovered that his right hand was connected to a mysterious space called the 'Catastrophe Containment Facility,' from which he could acquire the powers of the monsters imprisoned within!By capturing a vampire, he gained a formidable physique;By capturing a ghost, he could turn invisible and pass through walls;By capturing a fox spirit, he could charm the opposite sex...In short, in order to obtain more powerful abilities, Wen Wen began to diligently capture monsters, thereby stepping into the strange world of superpowers and seeing the hidden truths behind the curtain...

Saying 5000 year-old-dragon has an impressive ring to it, yet that dragon was an extremely harmless, herbivorous being. However, because of his uselessly giant figure and scary appearance, he was mistaken for the Demon King’s executive and provided by the nearby village with a sacrificial maiden.

Fundamentally cowardly and timid dragon tried to send her away, but the extremely enthusiastic sacrifice didn’t want to give up. Inevitably, he lied: “Okay, I just ate a small portion of your soul, so you can go back already”, but the maiden with outrageous assumptions has misunderstood that she became the dragon’s kin.

Then, out of all things, she began to manifest strange power on the basis of her wrong assumptions – in turn, the helpless dragon, by some mistake started a rebellion against the Demon King.

Rebellion or whatnot, he wasn’t even his subordinate in the first place.