Taboo Conquest of Lustful Emperor - Chapter 21 -

Rae, a perverted thief with bad luck and worse life choices, was caught peeping on a couple getting busy. Naturally, he got his ass kicked—and his life ended.Or so he thought.Just before his untimely demise, Rae had one last wish: to live like a king, surrounded by voluptuous women with big booties and even bigger breasts.Turns out, death wasn’t the end. It was just the beginning. Rae woke up in a fantasy world, and not just any world, but one where he was gifted a special system. A system... with some unusual tastes.[Ding!][Quest: Drink breast milk from the source.][Litres: 0/10][Reward: Race Change from Goblin to a race of your choosing.]“Wait—what? I’m a goblin now?!”

He is a young man without a spirit root. It is believed that this denies him the chance at cultivation. However, a mysterious lady imparts a Supreme Demon Classic to him and from then on, he starts his path of cultivation.
He undergoes a total transformation to emerge as the most fearsome and powerful fiendish demon in his era, that even immortals and fiends are fearful of him, and saints are at his beck and call.
Mastering the Supreme Demon Classic is the turning point in his life. He is able to unleash his immense and divine power from within, illuminating the entire universe!

- Description from Novelupdates

The world is up for sale, and Robin is making an offer.When Robin Waybright became the Merchant Hero, all of Pangeal turned into his marketplace; for the Merchant can buy and sell anything. Youth, skills, memories, hair color, joys and illnesses… in the trade of power, every deal can tip the scale.And Robin needs power. His homeland of Archfrost teeters on the brink of collapse, the sinister Demon Ancestors plot in the shadows, and twenty-one other Heroes, each with their own Class, have been chosen to save the world of Pangeal. Not all of them are friendly. There’s work to do… and profit to make.Cover by Dinovoila and Gharbi Zouhayer.