Love Kome to Kaiju Taiji no Fumonritsu

One day, a shy high school girl named "Tsubura Enjou" suddenly travels back in time to 50 years ago. For some reason, she ends up in the role of the hero "Justice Flare," here to fight off giant monsters! Back in the present day, 50 years later, Tsubura's childhood friend "Anna" and Tsubura's crush "Sho," both of whom are tokusatsu fans, are looking forward to seeing her "Fight on today! Fight on Tsubara Enjou!" This is crazy—! The start of a time-slip monster-extermination romantic-comedy that can't be explained by science alone.

(Source: TMS Lab, translated)