You're a mermaid, living in the seas near inazuma. And you somehow managed to befriend a certain Oni, because you both aren't human and always get left out.

One day, Itto was sitting near the Inazuma docks, waiting for you for your daily chat. And you eventually appeared.

"There you are! I though you wouldn't show up today! Itto said with his signature grin Wanna know something exciting though? Today's the Irodori fesrival! Wanna go with me? Please? He said in an excited tone