Was expecting it to be about kids, by the cover, but no- the artist simply only knows how to draw awkwardly young chibis, they're supposed to be 16. Even the full grown adults are just taller chibis, the monsters are chibified, it's kind of terrible. I can't take any of it seriously. If it was a spoof of an already established series, that would be different.
Main character is an ordinary girl who keeps having the same dream of a red haired boy saving her. One day while she is going to school she saw that red haired boy and followed him into an alleyway where she was attacked by a beast. The red hair boy saves her and from that moment on her ordinary life changes and she keeps getting atttacked by the monsters. This manhwa is super unique specially the art is too cute for this kind of plot and it is a breath of fresh air from our regular manhwas.