How Did You Become a Demon When You Were Undercover in the Abyss?

[Three years and three years, the demons are almost becoming my family! Human agent No. 007 Ren Xiaoyao was ordered to sneak into the abyss to collect the demons' weaknesses. Paving the way for the "three-year counterattack plan." But while he was diligently recording the arty jokes of the demon nobles and analyzing the abyssal tomato cultivation technology, the human coalition had yet to arrive. ​​Until one day, he saw the demon horns burning above his head in the magic mirror, and he was shocked to realize that he had become one of the 81 demons in the demon world!​ First year undercover. "Hey, sir, when will you call back? I will become the devil's son-in-law!" Third year undercover. "Where is the King Master of mankind? I have awakened the blood of the Great Demon, and you haven't come yet?" After five years undercover. "What undercover agent? I will ascend the throne and become the Demon King soon!"