The Retired Hero is an Extra - Chapter 22 - : Flutter

After spending his sixth year at Hogwarts a century ago, Harry finds himself back in the cupboard under the stairs in 1991, once again receiving his Hogwarts acceptance letter.“You’re telling me my parents were killed by a dark wizard?” Harry asked. “Who is this dark wizard? Why are you all so afraid of him that you won’t even say his name?”“It’s Vol—,” Hagrid began cautiously. “Well, we call him Voldemort, because he personally killed hundreds of people.”Harry nodded nonchalantly.“And what happened the next day?”Hagrid: “Uh?”--

Li Rui had lived to to seventy without any cheat or golden finger. Looking back on his life, he had gained nothing and accomplished nothing. Just as he’s been worn down by the years and resigned to his fate, he unexpectedly awakened the Perfect Life System.“Come on, tell me, how is a seventy-year-old man who’s about to kick the bucket supposed to live a perfect life?!”【You are born with the Martial Bone, and from the moment of your birth, you are destined to become the world’s number one. You gain the talent – Martial Bone.】【At the age of ten, you join a renowned sect and shine in the sect’s grand tournament, gaining fame and attracting the attention of an immortal teacher. You acquire the talent – Divine Skill Mastery.】Looking at 【Gains the favor of an immortal maiden, becoming a divine couple】, he fell silent.“Seventy years old is just the right age to start doing things!”…Many years later.Li Rui finally emerges with the supreme innate Dao fetus, slaying ten thousand demons, breaking ten thousand evils, and ruling over the immortal realm for a hundred thousand years. He is hailed by the world as the Evergreen Immortal Venerable.

As a man who had lived for 20 something years and had always considered himself as a straight man, he woke up one day and found himself possessed by a stupid and cute system. Moreover, it was a gong-shou cultivating system?! Let’s see how a shou with raised hackles evolves into a (pseudo)queen shou, incidentally with a story of a hidden loyal dog gong.

- Description from Novelupdates

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.