Five years after Jemma Simmons and Leopold Fitz signed on to become Agents of S.H.I.E.L.D., the words "Will you marry me?" were spoken. Fittingly, they both asked each other (but it was Jemma's proposal that 'counts', as she couldn't hear Fitz when he asked). After all this time of being literally star-crossed, separated, reunited, but never wavering in their commitment to each other, fans of Marvel's Agents of S.H.I.E.L.D. have been promised the wedding that we - not to mention Jemma and Leo themselves - have long pined for. A wedding that will seal what we all know to be true: FitzSimmons is the greatest romance in the Marvel Cinematic Universe.
Portrayed with unmatched chemistry by Elizabeth Henstridge and Iain De Caestecker, no one else in the decade-old MCU can compare to FitzSimmons. Marvel may be the very finest at delivering superhero blockbuster movies with characters fans have fallen in love with, but romance is not the MCU's forte, and never has been. This was evident right at the MCU's inception with the love affair between Tony Stark and Pepper Potts. Pepper was originally the long suffering personal assistant subservient to her boss Tony's whims, eccentricities, and sexual dalliances. Even when Tony declared his love for Pepper and promoted her to CEO of Stark Industries, they were hardly equals. Arguably the only one who really admires this pairing and desires a storybook ending with Pepper is Tony himself. And this is the foundational romance of the MCU.
The rest of the Marvel movie pairings aren't any more inspiring, save perhaps for the fleeting and doomed World War II romance between Steve Rogers and Peggy Carter. Steve and Peggy simply didn't have enough time, with fate cruelly creating a situation where Steve remains young and vital while Peggy lived a heroic life for decades without him, aged, and died - though they briefly and sweetly reunited. As consolation, Steve has sparked a romance with Peggy's much, much younger niece Sharon Carter, but even they have been kept apart as a result of the Avengers' Civil War.
In terms of the other major MCU romances, Thor and Jane Foster started off strong but went kaput. Fans really did not care for Joss Whedon's attempt to romantically pair Natasha Romanoff and Bruce Banner, nor is anyone particularly rooting for Dr. Christine Palmer to end up with Doctor Stephen Strange. The jury's out on Scott Lang and Hope Van Dyne, and Peter Quill doesn't seem to have much of a shot with Gamora, despite his childish efforts. For everything the Avengers and the Guardians of the Galaxy get right as superhero movies, those looking for a genuine love affair between these beloved characters must look elsewhere.
The love stories found throughout Marvel Television aren't much better. Matt Murdock's relationships with Karen Page and Elektra Natchios are both disasters. The comic book marriage between Jessica Jones and Luke Cage hasn't materialized; Cage is romantically involved with Claire Temple, though this seems to be a relatively solid coupling. Fans are left bewildered by what exactly the capable and admirable Colleen Wing sees in Danny Rand. Meanwhile, within Agents of S.H.I.E.L.D., Phil Coulson and Melinda May's unspoken but deeply felt relationship has been simmering for years, while Daisy Johnson has been so unlucky in love, it's inhuman. At least, Mack McKenzie and Yo-Yo Rodriguez seem to be forging a real connection, though they're understandably taking it slow.
In regards to Marvel romance, FitzSimmons is the pinnacle - and deservedly so. It's safe to say they were literally made for each other. Even from the very beginning of the series, fans and the characters themselves were in immediate agreement: we all wanted to see FitzSimmons together. They were simply adorable together: both squeaky-clean young scientists from the UK launched into the world-saving adventures of S.H.I.E.L.D. That they started together as colleagues who shared not just a fondness but a mutual respect - she a biochemist with numerous Ph.D.s and he a genius engineer who created little robots and desired a pet helper monkey - only made their connection sweeter. They were a team within a team, two peas in a pod, so much so that Coulson coined the name and introduced them as "FitzSimmons". Even early on, they were one, but neither felt they were in a position to express and pursue the obvious.