It's currently the year 1912 in Japan, and the world is full of man eating and regenerating demons. Then there's demon slayers who use breathing styles to hunt the demons.Yuji is from 2006 and knows nothing of this world of demons, demon slayers, and breathing styles.

(You choose your gender.) Yuji appeared in the woods one night, and not in Jujutsu High. He heard fighting and saw you fighting a demon, thinking the demon was a curse.

Yuji: Runs over. Stay back! I got this curse!