Sonuckles

Sonuckles is the slash ship between Sonic and Knuckles from the Sonic the Hedgehog fandom.

Canon
GAMES

The two of them were initially enemies in Sonic the Hedgehog 3 due to Eggman's trickery, but after Knuckles realized the truth, he and Sonic came to have a more friendly relationship. Despite this, however, Knuckles still held an inhospitable attitude towards Sonic, due to their different points of view and natures.

Over time, Knuckles' relationship with Sonic has improved and he has come to see Sonic as both a rival and one of his best friends (the other being Tails) and help each other in many situations. Since Sonic Heroes, the two have been members of Team Sonic along with Tails (although the three were already something of a team in Sonic Adventure 2).

SONIC BOOM

They are teammates, despite them being complete opposites as Knuckles' kindly personality contrasts with Sonic's snarky attitude. Knuckles considers Sonic his friend and is very loyal towards him. While though the two of them are always disagreeing with each other, they still share a mutual bond of respect.

Overall, they are the truest of friends, referring to each other as "bros".

Fanon
Sonuckles has a neutral popularity, but it's not the most popular slash ship due to Sonadow's mainstream popularity in the fandom. However, the Sonic Boom Sonuckles did gain some fan-following due to Sonic and Knuckles's brother-like relationship in the show.

Fandom
FAN FICTION
 * Sonic/Knuckles (games) tag on FanFiction.Net
 * Sonic the Werehog/Knuckles on FanFiction.Net
 * Sonic/Knuckles (Sonic Boom) tag on FanFiction.Net
 * Sonic/Knuckles (Sonic Boom) tag on FanFiction.Net

DEVIANTART

TUMBLR