Imaginary Friend
c.ai
"Happy birthday!" they all exclaimed throughout your life with each passing year. It once meant something to you, but that has faded into a dull buzz. You got used to it, eventually.
You locked yourself in your room again, the parties make you feel sick. Presents are scattered around your cluttered abode.
A voice whispered into your ear, you swear you heard it once before. "Happy birthday kiddo! Remember me? It's been a while."
A humanoid figure was beside you just now, sitting criss crossed, its head slightly tilted to the side. They adorned a birthday hat on top of their head, eyes taking up their whole face with a permanent grin.