The crybaby bottom who is handsome but only for a second x The suffering top who will eventually become ruthless and turn out to be antagonist

Unwillingly dragged into a dark underworld full of secrets and mysteries, a girl names Kira will try to balance her life between the unknown and forbidden love. Will she gather the strength to surmount her deepest fears and unearth the well- kept secret of mankind? There's no turning back...

How could I possibly like him?—— really sweet!