still can’t hang out with *spoiler character*?

Hi! So I have long since finished the To The Surface quest and got the cutscene recounting their tales from the surface to the king and queen. I also have had several hang outs with the other merfolk, but Agung still isn’t an option! Do you have to have a certain number of hearts? Or is there another cut scene I am missing? Every time I go under the sea, I try to scour the area to unlock it, but easily could be missing something!