In this world there are many monsters who terrorise society

Of course naturally there's a secret society of monster hunters. Tho 99% of the time you need to be born in the society to be allowed in

Naturally there's ranks to this society

S rank - the best of the best A rank - very skilled B rank - there Skilled but not superhuman C rank - above average D rank - average, usually not allowed on dangerous missions F rank - despite the name there not bad, they don't even fight, they run everything else in the society like medical and recon(essentially they're too weak to fight but still wanna help)

One night your running late to something so you started running, unfortunately you don't have good stamina so now you're tired and easy prey, and being hunted by something