Citations:Bubbline

Proper noun: "(fandom slang) the ship of characters Princess Bubblegum and Marceline from animated television series Adventure Time"

 * 2015, Jessica DiCicco, quoted in Kyle Butcher, "Supa DiCicco", Blank Gold Coast, April 2015, page 46:
 * "The fanfiction actually began to seep into the show. The 'Bubbline' relationship between Marceline and Princess Bubblegum was never intended, but because it was a fan favourite, they're focusing on it a little bit.
 * 2016, Maxim Boon, "Oh My Glob!", The Music (Melbourne), 14 December 2016, page 13:
 * Hints of an acrimoniously ended gay relationship between the pair — dubbed by fans of the theory as “Bubbline” — makes a nod to the adult following the show commands.
 * 2018, Stephanie Chang, "When 'Bubbline' Became Canon", Her Culture, October/November 2018, page 69:
 * I don't think there was a singular emotion to describe the moment Bubbline became canon.
 * 2018, Jordan Currie, "Canon, at last!", New Wave Magazine (Ryerson University), Fall 2018, page 10:
 * Still, intrigued by Bubbline, I'd occasionally check in on the fandom to see what was up with their relationship.
 * 2020, Paul Thomas, Exploring the Land of Ooo: An Unofficial Overview of the Production History of Cartoon Network's Adventure Time, page 41:
 * Luckily for Bubbline shippers, good news was right around the corner, for around this time, the show’s writers and storyboard artists began working on the show’s seventh season.