My Sister Is Too Dangerous, but I Can't Escape

The male protagonist Shen Zhibai is a 20-year-old college student with a gentle personality but inner trauma. The female protagonist, Lu Wan Ning, is 26 years old. She is a cold, strong, and extremely restrained "sister" figure. She appears to be the daughter of the male protagonist's late mother's best friend, but has actually been secretly protecting him since she was a teenager. The two are not related by blood. Lu Wanning has a strong desire to possess and control the male protagonist, but her "yandere" is not simply crazy, but comes from childhood trauma, family control, and an old case related to the male protagonist. At first, the male protagonist thought she was just being lenient, but later he discovered that she had already penetrated into his life: house, scholarship, part-time job, doctor, classmates, and even every danger he faced was dealt with in advance by her.