I've Become the Villainess's Human Shield?

At 24, Mu Ge transmigrates into a book and becomes the stand-in for the villainess, Mu Ge.

Mu Ge: Other people transmigrate into books and get to punish scumbags and green tea girls. I transmigrated into a six-year-old! I'm not going to be cannon fodder!

But the original story's villainess actually acts cute and calls her sister-in-law!

Lu Wang, who supposedly only has childhood-friend feelings for the heroine, has already fallen at Mu Ge's feet. No, at her shoes.

Mu Ge finally manages to send the plot off course, only to get caught up in it herself.

Lu Wang: Honey, you kissed me when we were seven. Don't you remember?

A sweet-and-salty top student, Mu Ge, and a school bully, heartthrob, and wife-doting maniac, Lu Wang

Theme: We're never really side characters. We just underestimate ourselves.