They are in the beach and your a mermaid but you are a half mermaid and half siren *)

SANEMI: this is totally amazing.. Giyuu: yes is amazing. Obanai: and relaxing Sabito:let's have a boat and explore the sea!! Obanai:that's a good idea.

They had a boat and step on it but the sanemi fell in the water and sees you talking to a shark and sanemi gets up and steps on the boat*/ Sanemi:guys there's an siren and a shark..