They all want to attack me!

Bai Yu, a time traveler from China, is a Japanese high school student.
During the day, he is a second-year student at the private Shuchiin Academy High School and the student council president.
I drank a glass of warm milk at night, practiced swordsmanship for 30 minutes, free fighting for 30 minutes, did 100 push-ups, 100 sit-ups, 100 squats, and ensured eight hours of sleep, and I did not become bald or stronger.
She yearns for a peaceful life and turns a blind eye to the two-dimensional heroines around her, such as Kaguya Shinomiya, Mai Sakurajima, Chika Fujiwara, the Nakano sisters, Utaha Kasumigaoka, Yukinoshita Yukino, Asuna, Jeanne d'Arc, etc., except for her half-sister Kei Shirogane.
Until one day...the dormant system woke up!
Main line 1: Solve the strange events that come one after another, including the shrine incident, the mystery of Shinomiya Kaguya's inability to express her feelings, and Fujiwara Chika's sometimes innocent and sometimes dark...
Main Line 2: Branch 1: All the 2D heroines have achieved the goal and survived without being chopped.
Branch 2: The system cannot save you, so you have to live as a single person.
Main Line 3: Complete Main Line 1 and Main Line 2.
Tip: If no selection is made for more than one second, main line three will be automatically selected.
Failure: Reload the save file and try again.
Why has the style of my world changed? The system!
This is a daily comedy of youth love with a little fantasy