The Great Demon System - Chapter 442: An Unexpected Hero.

Due to an unexpected turn of events, Xia Fei consumed a Super Gene Optimization Fluid that bore no brand, expiry date, instructions or stated its place of origin.
Our story begins here…

Zhuang Feng is in his last year of high school, and he’s just moved to the city. He lives with his good-for-nothing cousin, who’s always on business trips falling for get-rich-quick scams, and his Saozi (sister-in-law), who tries to make his life miserable as much as possible. There’s one upside, though; she. is. freaking. hot. But one day, he found a piece of her underwear in the bathroom…. And unfolded a series of events that will turn his life upside down.

- Description from Novelupdates

Chatting in the dormitory at night, roommates wonder how much pain Aunt Flow brings. Mr. Perfect He Zhi Zhou has never bothered joining in on these petty talks for amusement. That is, until he became a woman and laid in bed with a white-cast complexion……

Chatting in the female dormitory at night, roommates sighed over the current pairings in the school of engineering, Shen Xi was a little curious that the problem with these topics is that there was no way to test them. Until she became an engineering male and a bar of soap dropped in front of her……

Introduction in one sentence: About how a top-scoring perfect male with no desire in the opposite gender and an amusing female lead were set up like lightning setting the ground on fire spreading out of control—leading to a sweet and rippling life……

Life is so long, don’t be so arrogant. Some things are bound to deviate.