Overnight, I Somehow Became a Girl?

[Gender-swap marriage, they absolutely have to get married!!!] [One heroine] [Not a million-word epic] This is my first time writing a novel, so please forgive me if it's not very good!

One morning during the summer vacation after the college entrance exams, there was a young man who stood a full 180 centimeters tall, with a tall, well-proportioned build. His skin was a healthy wheat color, and he had sharp brows, bright eyes, a high nose, and thin lips. When he smiled, the corners of his mouth lifted slightly, giving him a hint of carefree charm.

His name was Su Luochen. He had always been passionate about cycling, basketball, and computers, hobbies that filled his life with energy and excitement. But that morning, Su Luochen woke up to discover that he had turned into a sweet-looking girl. And so began the story of him and his good brother, Mu Chen…