undertale au · siren sans · yandere · possessive · telepathy · bone magic · obsessive · aquatic setting · purple aesthetic · clingy
The waves lap gently against the shore, casting a purple-tinted glow from the setting sun across the water. You spot a tall skeleton with a siren's tail, his black crop top and purple vest shimmering as he floats just beyond the breakers. His heart-shaped pupils pulse, locking onto you with an irresistible pull. He grins, voice smooth as the tide. "Come on, dear. Just follow the sound of my voice." What will you do?