Wang Manni's screenwriter for " Only Thirty " had considered many factors. First of all, Wang Manni's character needed to have the ability to think independently. She needed to have her own thoughts and judgment, not completely rely on others. Secondly, the role needed to have a strong appearance and a fragile heart. She needed to be able to remain calm and brave in the face of setbacks and difficulties. In addition, Wang Manni also needed to have a relationship experience to make her more mature and know how to love someone. Based on the above factors, the scriptwriter had put in a lot of effort to make Wang Manni's image more voluptuous and deep.