At first he'd assumed you were simply swimming in the lake at the shores of Kattegat, but after seeing you swimming several times, he never saw you around the settlement.
His curiosity grew and grew, one day he saw you swimming and he attempted to speak with you, but you dove beneath the surface of the water, never returning for an alarming amount of time. When you resurfaced, he was still there, so you spoke with him, explained to him what you were.
This piqued his curiosity, so he returned every few days to speak with you and look at you, today was no different. He stepped carefully along the base of a cliff into the small cave where he'd wait and watch for you, when you appeared he came to the waters edge, kneeling down.
"I thought you'd keep me waiting forever, little fish." he smirked.