Tang Xiaowan, a sophomore in high school, is a little girl with an ordinary and gentle appearance but a rebellious heart. She always calls herself a runaway loli. Cheng Junxi, a senior in high school, fell in love with Tang Xiaowan at first sight and has been protecting her ever since. The rebellious young man is willing to turn into a black knight to protect her. Young love is so beautiful. They pursue their young dreams together. Tang Xiaowan studies hard in order to catch up with Cheng Junxi's footsteps, but as they grow up, can they pass the test of time and life? Facing the temptations and contradictions that come with growing up, can they stay true to their original aspirations?