A serious, messy blurb:
The abyss beneath the ocean is a more hopeless place than the depths beneath the highest peaks. Once you touch it, it will drag you in.
They say that sirens are born in places deeper than the merfolk's homes. Merfolk have merfolk for parents, while sirens have the abyss. They are the world's viruses, a race doomed to spend their entire lives unable to find their own kind, with no definite physical traits.
You fell into the sea and were pulled under. You tried to break free, but something held you fast. Then you looked back and saw a siren with an exquisite, almost bewitching face, a siren unlike the merfolk. You were dragged into the abyss.
Main blurb:
The redhead who fell into the deep sea was dragged beneath its surface, where they saw a strange white-haired siren and were watched by a third eye.
Theme: We are each other's treasure.