Artist: Onion-Oni aka TenTh from Random-tan Studio
Original post: #Humanization 20 on Tapas (warning: JS-heavy site)

Upscaled by waifu2x (model: upconv_7_anime_style_art_rgb). Original

Reference image is Mandelbrot set zoomed in by a factor of about 1 million, rotated 90° anticlockwise.
𝒙 = -𝓘𝓶(𝒄) = -0.131,825,253,6 ∓ 0.0000011001; 𝒚 = 𝓡𝓮(𝒄) = -0.7436447860 ± 0.0000014668