Science and engineering top student Lin Mo drops out of university to raise his daughter Niannian alone, making a living by setting up a stall to repair and sell toys at the university town night market. A scene where his three-year-old cute baby gifts a toy to campus belle Su Wanqing is filmed by a passerby, unexpectedly going viral across the entire internet and disrupting the peaceful life of the father and daughter. Lin Mo sticks to his bottom line and starts live streaming, gaining fans with his solid craftsmanship. Ye Wange, president of the Ye Group, appears to reveal Niannian's identity, and both parties reach an agreement on joint custody. Lin Mo and Su Wanqing gradually develop feelings for each other, joining hands to create the "Little Sun" toy brand, fighting their way up from a night market stall. Achieving success in both career and romance, they harvest the stable happiness of the mortal world's fireworks.