The practice of shipping characters is a common occurrence in any dedicated fandom, especially one as large as the Transformers. However, something that is not common is for a previously non-canonical fan-ship to be embraced by a creative team and made canon. During the Transformers Prime television series, a popular fan-ship arose between the Decepticons Knockout and Breakdown. Their comedic banter and close friendship made them an oddity amongst the villainous Decepticons, inciting the fan belief that they were perhaps more that just friends.
Their relationship was unable to go beyond a platonic friendship before Breakdown died in the show's second season. In 2015, IDW Publishing decided to implement the fan-ship following the continuity of the 2005 TV show. Writer Mairghread Scott introduced a Transformers Prime inspired version of Knockout into the Transformers: Windblade series as an unaligned Cybertronian. During the story, Knockout casually commented that he had a 'conjunx endura' --a Cybertronian term for a significant other -- with the implication that it was Breakdown.
Breakdown and Knockout's romantic relationship was officiated in 2015's Transformers: Windblade #4 (by Mairghread Scott, Corin Howell and Thomas Deer) during a tie-in to the Combiner Wars crossover event where a Transformers Prime inspired version of Breakdown made his first official appearance. Breakdown was explained to be another unaligned Cybertronian from the planet of Velocitron, being considered a slow-moving member of a planet that highly valued speed among its citizens. Despite facing prejudice for his lack of speed, Knockout developed romantic feelings for Breakdown and the two commenced a relationship together. When Knockout became the political representative of Velocitron, he and Breakdown moved to their ancestral home of Cybertron, where Knockout believed his partner would find less prejudice for his bulky physic and lackluster speed.
The couple would continue to make frequent appearances throughout the rest of IDW Publishing's Transformers comic series, appearing in The Transformers Holiday Special where the two took a romantic trip to Cybertron's Acid Wastes and helped defend Cybertron from hordes of undead Titans, Knockout using his speed to lure Titans to Breakdown's artillery in Transformers: Till All Are One #5 (by Mairghread Scott, Sara Pitre-Durocher, Priscilla Tramontano and Joana Lafuente). When the original IDW Publishing Transformers comic book series came to an end in 2018, Knockout and Breakdown stood side-by-side with Optimus Prime and hundreds of characters in the finale miniseries; Transformers: Unicron (by John Barber, Alex Milne and Sebastian Cheng).
Knockout and Breakdown's romantic relationship has recently made a reappearance as a part of IDW Publishing's new Transformers comic book continuity that started in 2019. During the comic miniseries Transformers: Wreckers - Treads & Circuits (by David Mariotte, Jack Lawrence and Candice Han), Knockout participated in the massive Speedia 500 race to determine who would become the new leader of the planet of Velocitron. When the terrorist organization known as the 'Mayhem Attack Squad' attempt to sabotage the race, Knockout was saved by his significant other who was acting as the Security Chief of the race. Breakdown managed to shoot the Mayhem Attack Squad member known as Axer when the terrorist tried to kill his lover in the middle of the race. However, the end of the miniseries revealed that Knockout and Breakdown were working in cahoots with the Mayhem Attack Squad to sabotage the race so that Knockout could win and make the planet of Velocitron a Decepticon fief.
With more appearances of this couple beyond their initial debut, it would appear that the romantic relationship of Knockout and Breakdown has been fully cemented into Transformers lore, with many fans overjoyed to see this originally fan-based ship take form as a legitimate pairing. With the two set to return in future IDW Publishing comic books, it is clear fans will be seeing more of the duo in future installments of the Transformers franchise, potentially they could even make an appearance in the forthcoming Transformers: Earthspark television series on Nickelodeon.