Welcome to Ward 816, a place filled with incredible children who are true warriors. Each of them carries a badge symbolising their strength in fighting various diseases. In this bustling ward, there's a special group, including Yuan, Shi-yan, Heng, Nuala, Jia-nong, and Da-shan. Despite their parents' occasional arguments, they always come together to support one another when it matters most.
On a cold Valentine's Day, a girl Xiao-Hua runs into a boy A-Wen who is waiting for his lover. Out of empathy, Xiao-Hua hands A-Wen a cup of hot milk tea. The two get to know each other since. On the same day, Zi-Jie Huang also bumps into Xiao-Hua. Zi-Jie behaves like a jolly charming womanizer, which makes Xiao-Hua uncomfortable. There are already frictions between the two at the first sight. Xiao-Hua is convinced that A-Wen's lover must be Yi-Chun, known as Butterfly. Out of surprise Xiao-Hua discovers Yi-Chun cheats on A-Wen with Zi-Jie. She feels even more sympathetic to A-Wen. Xiao-Hua later realizes that Zi-Jie never gives his heart to anyone, because he could die at any second. After Zi-jie confesses to Xiao-Hua his love for her, Xiao-Hua’s ex-boyfriend Shao-Ping unexpectedly reappears and stirs up her peace. When Xiao-Hua finally admits her feeling for Zi-Jie, Zi-Jie is ill. Winter is coming to end, will there be a happy ending at the end?