Itai no wa Iya nanode Bōgyo-Ryoku ni Kyokufuri Shitai to Omoimasu - Chapter 395

One day, Zhang Fan, a poor medical student, receives a medical system from the future. This turns him into a new shining star in the medical field. Along the way, he must face medical corruption, competition, and infighting from other doctors, and even find time for a love life as he strives for the top of the medical field!

- Description from Novelupdates

[Invincible, showoff, face-slapping, feelgood]“Who is richer? Sorry, Every watch I have is worth billions. Money is just a number to me!”“Wanna fight? Fine, I won't even use my hands and feet. I've never lost a fight in my life!”“You like me? Sorry, even a cruise ship is not big enough to hold all the women I have. Haven't you seen the princess of Anenida lining up for me?”With the invincible system, everything can be easily accomplished.Please don't show off in front of me. I have a nickname called Face-slapping Zhang!

I’m in a secret, bad romance with a love dependent student—「Having a secret meeting with a student one is in charge of at school… Isn’t it exciting?」The special relationship with Kirihara that no one can know about began when I took up my post at Mori Kawara High School as a teacher.At school, she’s the serious student council president who has earned a lot of trust from other teachers, but when it’s just the two of us, she becomes mischievous, clingy, and jealous.On weekends, I cook meals at her place, play games together, and pamper her as if we were lovers.Unable to reject her because she knows my weakness, and despite knowing it’s wrong, we continue to pile up secrets little by little every day…「Sensei, my feelings of liking you have grown very strong.」As Kirihara openly confronts me with her feelings, the emotions I’ve been holding back grow even stronger.Even though it would all be over if it were exposed, that sense of immorality ironically only accelerates things further—

Du Fei was reborn, and in this difficult era of extreme shortage of supplies, he started his wonderful life of opening and hanging…

- Description from novelbuddy