The boardwalk was noisy in a human, jostling sort way. Not that the beach and ocean were quiet. Cetin noticed an attractive Asian girl down by the surf, picking through pebbles. Alone. Ah he should check that out.
"Ho, there! You all alone?"
The girl looked up, then glanced into the ocean spray. "You could say that."
The ocean seemed more ... there ... than normal. After Cetin had climbed down to the beach he squinted at the ocean and felt a certain unease.
"I'm June," she said.
"Cetin."
"Satan?"
"No. Hah. But same root word. You ever feel the ocean is watching you?"
"Ah you can feel that? That's Yzgrndl. I'm not alone."
Cetin stared. There was just ocean, and crashing waves, and spray. Jumbled sounds of the boardwalk echoed above. The menacing feel was stronger.
"What the hell? What is going on here?" he asked.
"Ooh you tell me. Is it the ocean?" asked June.
The waves crashed. Receded. Came in, crashed again. The menace ...
"It's not the ocean?" he guessed. "It's separate from it. Straight out to sea, it's almost not there." Cetin glanced around. "Over to the left feels strongest. But how does that work?"
"It's just Yzgrndl, like I said." She picked up some seaweed, rubbed it against her face, tossed it into the waves. "I think he's adopted me."
Cetin decided June wasn't an easy mark. Someone to be treated with kid gloves, if at all.
"What do you mean adopted you?"
"He thinks I'm his daughter," she giggled.
"Are you?"
"Oh no. I'm just me. Human and all."
"Why does he think you're his daughter?"
"Just my thought patterns, I think? It seems it's an easy mistake to make. It's happened before. He thinks I'm cute."
"Mmm, I wouldn't disagree."
"But you think I'm cute because I'm young and female and unattached. He think I'm cute because I see you as a bag of water and sticks who teetered down here from that big xylophone." People's footsteps on the boardwalk mixed with the sound of the surf. "Being human is just an interface, if you master the interface it doesn't matter what's inside. So you see me as a cute young girl, you see? But he sees what's inside. I suppose it's just another interface yah? But with him it's from a totally different angle, and he thinks I'm one of his own."
"So, what, does he live down here? Are you visiting him?"
"No no he follows me around. Sort of a helicopter parent, you know? I like the ocean, it's a strong personality and more than Ysgrndl can counter." She came closer and spoke softly. "You should probably go back, you know, or you might get eaten."
"You are very strange."
"Why, thank you!"
Cetin decided he was enjoying this. He grinned and addressed the menacing mist. "Oh great Yzgrndl," he opened his arms, "will you grant me permission to speak with your daughter?"
There was a roar, and a solidifying, and a spattering of blood. Cetin was gone.
June listened a bit. "Oh he was a bit pushy I agree. But I still wish you wouldn't do that." She picked up more seaweed and tasted it. Wonderfully salty. But the sand would wear down her teeth. Humans are so fragile she thought. Like sandcastles. Yzgrndl was too of course but in a different way. Hm maybe if she had diamond teeth. No, better self repair ...
This was in response to reddit.com r/WritingPrompt, "You just learned that the eldritch monstrosity haunting your dream has in fact 'just' mistaken you for its young, and is trying to parent you in its own inscrutable ways." I ignored the dream part.
I liked the idea of June being inherently stranger than the eldritch monstrosity. Where the monstrosity mistook her for an eldritch horror, but actually no that's undershooting, he's the one who should be horrified of her. I don't think I did June or Yzgrndl justice here. June is both acting a little obviously strange (she knows not to) and isn't internally nearly strange enough. If this continued, likely Cetin would end up teleported across town with a nosebleed rather than actually eaten. Why would Yzgrndl care about eating anyone? Wrong biochemistry, yah? Boys kill ants just for the thrill of killing something, it could be that, but Yzgrndl eating random people will get June in trouble with the human authorities. You could have June luring overly-hormoned boys to their death to sate Yzgrndl's appetite, but that's depressingly human behavior for both June and Yzgrndl.