My Loli Senior Is My Mom?!

After losing both his parents and then his stepfather, he gets a call from a stepmother he's never met, asking him to bring her a blanket. When he rushes to the school gate, the person waiting for him is a petite girl with twin tails who barely clears 1.5 meters—none other than his sophomore-year loli senior! Stunned, he can't help but scream internally: My loli senior is actually my mom?!