Why Is the Vicious Female Supporting Character in a Book Still a Tomboy?

[Traveling through the book/former boyfriend and then transformed/turned into a hundred/1v1/system/chasing wife crematorium] Lin En is an ordinary college student. He was hit by an oncoming truck while crossing the road while playing with his mobile phone. When he woke up, he found that he had been reborn as a vicious female supporting character in a novel about a domineering president, and she was also a boy and girl. "The heroine is also reborn" It's a crazy start. You have to please the heroine while hiding your gender. The introduction is too weak, let's move on to the main text!