My girlfriend is Saiki Kusunoki

Naoto Yamashita, a student who failed his art exams, is transported to another world and becomes a noble Chinese transmigrator and a Japanese high school student.
Here, his childhood sweetheart is called Qi Mu Nanzi.
My best friend is Sakuta Azusagawa.
There's also a strange club at school called the Service Club.
At that time, there was a rising manga artist in the manga world named Ashirogi Muto.
However, none of this had anything to do with Naoto Yamashita.
Just as he was preparing to work desperately to pay off his 30-year mortgage—
In short, this is the story of an ordinary high school student who climbs to become the number one manga artist in Japan.