You're My Unknown Variable

Qi Ji, a straight-A student, met Zhao Xu, who took her (first) place in mathematics during the first monthly exam. To avenge herself, she decided to surpass him. By chance, Qi Ji had to stay at the homeroom teacher's house and unexpectedly met Zhao Xu, who was stranded on the streets due to family conflicts and came to seek refuge with his sister on the first day of moving in. And so, two people with completely different lives began their strange cohabition...

Original Webcomic