Others have traveled through time and become protagonists, dominating the world. Lead a group of little fanboys and little fangirls to defeat bad guys, help civilians, gain a harem, and reach the pinnacle of life.
Even if his life is bad, he can still be an assist, and he can hug the protagonist's thigh or something.
But, how did I travel through time and become a system? ! ? ? Is there any mistake? ! !
Purpose: To help each other in the same boat