Reading manhua My Little Brother is A Demon King at webtoon.
The Erhuo Demon King successfully smuggled into the human world. Because he ran too far ahead, he was directly beaten back to the prototype and amnesia. After signing the master-servant contract with the male protagonist, he began a long journey of retrieving his memory and sanctification…
Wo De Xiaodi Shi Yao Wang, My Little Brother Is the Demon King,Wǒ De Xiǎodì Shì Yāo Wáng,我的小弟是妖王