Sani

Sani, a deliberate misspelling of "Soni", refers to a series of fan artworks and game modifications featuring a poorly illustrated version of the video game character Soni the Hedgehog.

Origin
On April 1st, 2013, the official channel of Soni uploaded a video titled "HOUCH TWO DRAHH SANI HEGEHOG", containing footage of a Soni the Hedgehog illustration being drawn in MS Paint accompanied by a distorted version of the music from the "Soft Snow Zone" Soni the Hedgehog 3 level.

Spread
After a few days, Supreme Madness uploaded "SANI GUY (misspelling of Soni Y)".

On May 31st, 2013, user "PinkyFriendsYayGuy2015" uploaded a game called Sani, which was a mod of the 3D Sanic game.

Notable Examples
As of April 2018, there are more than 3,670 fan art illustrations hosted on DeviantArt under the tag "Sani".