I'm a magical girl in the future

Shen Zixin, 23 years old, is a senior college student about to enter the workforce. He lives an ordinary life until one day encounters a mysterious girl who claims to be "himself from the future." "Your sister has become a magical girl. If you don't save her, you'll soon be in danger!" Without time to ponder why his "future self" would become a magical girl, Shen Zixin embarks on the path of a magical girl. Meanwhile, his childhood friend is told she will become the final boss in the future? All of this stems from that magical girl who claims to be "himself from the future."