Rookinite

Rookinite is the Non-binary ship between the Avatar and Infinite from the Sonic the Hedgehog fandom.

Canon
For months, the Avatar and Infinite fought on opposing sides of a war. The Avatar was among the soldiers defending their city, although too scared to fight in the front lines, while Infinite was the commander of the Egg Army.

The Avatar and their quadron got attacked by Infinite. Infinite killed all members of the quadron except the Avatar. The Avatar tried to stand against Infinite, but he clearly noticed their fear. Infinite gave the Avatar the option to get out alive of the ran away in fear, which they did. The Avatar ran into the Resistance headquarters, and eventually joined the group to help free the world from Infinite and Eggman.

Infinite and the Avatar later met again in Metropolis. Again, Infinite tried to terrify the Avatar. However, due to words of encouragement by Sonic, this time, the Avatar did not give into their fear but rather fighting Infinite. During the fight, the Avatar was protected by a Phantom Ruby prototype. After the fight, Infinite allowed the Avatar to live yet again to let them continue to be in fear as he knew Eggman would destroy the Resistance soon anyway.

Later, the Avatar and Sonic fought Infinite for a final time. They managed to beat Infinite for good, causing him to vanish into thin air.

Fanon
A popular version of this ship is known as Infidget, in which the Avatar is a red male wolf (the form featured in promotional images of Sonic Forces) and named Gadget, a fanon name for the character. As such, this pairing is more commonly shipped as slash than het. Meanwhile, Rookinite is a more general term referring to any Avatar x Infinite pairings.

The pairing has gained popularity as the two debuted in the 2017 game Sonic Forces, one as a main hero (besides Sonic) and one as a main villain. This ship is the most popular ship for both characters.

Fandom
DEVIANTART

Trivia

 * The ship name "Rookinite" comes from Avatar's nickname Rookie, which is a name characters use to refer to them in-game.
 * The pairing can be either het or slash as the Avatar's gender is chosen by the player.