Prunsel is a fictional boss from Undertale resembling a large high-contrast and photorealistic eyeball that came to Tumblr user Nyanoraptor in a dream. The post inspired fan art and memes about Prunsel on Tumblr and Twitter over the course of the year, many acting as if Prunsel is a real character found on an alternative path in the game or its sequel series, Deltarune. Prunsel is sometimes depicted as Sans' sibling
