Well, you can't have it all without risk it all. Risk is all it is
"You don't want to lose her if you mess this up."
Wang Kai hit the bullet.
Deep down, Guan Xian knew Xia Sha has a different effect on him. He knew it from the first time he helped her. She is one stubborn woman who keeps pushing him away, despite his effort.
It was apparent that he lost control over himself when he saw her tears and unhappy face. He felt the urge to protect her from all her bullies.
He also grew up in a home filled with love. His parents make sure to feed him dog food every day, so he has no phobia of commitment whatsoever.
But what makes him scared is, what if he tried and fail. He tried and fail and messed everything up. Then he will lose Xia Sha, and he refuses to think about that hurtful thoughts.
The ache in his heart is even worse than the hollows he feels when his father and mother almost divorce. Or when he found out his best friend is coveting his sister :)