The Marvel Universe is no stranger to superpowered romances, from the Fantastic Four's classic pairing of Reed Richards and Sue Storm to the tumultuous relationship between Mystique and Destiny. Of course, not every relationship is built to last, nor are they all capable of changing the course of history all on their own. On the other hand, there is no shortage of romances that have come to shape not just the characters involved in them, but the world around them as well. Or, in the case of Marvel's most important love story, reality as it once stood.
Every corner of the Marvel Universe has had its own power couple over the years, all of whom have helped to define their respective eras. As influential as these other Marvel couples have been, there are none that have had nearly the impact as Peter Parker and Mary Jane Watson.
Mary Jane Watson has been an indelible part of Peter Parker's life ever since her first full introduction back in 1966's Amazing Spider-Man #42 by Stan Lee and John Romita. MJ's presence in those early years provided plenty of drama between herself, Peter, Harry Osborn, and Gwen Stacy. In spite of this, it wasn't until after Gwen's untimely demise that M.J.'s relationship with Peter was cemented a decade later in the pages of 1976's Amazing Spider-Man #156 by Len Wein and Ross Andru. At the time, their coupling was something of a relief for fans who had been waiting for their story to finally come together, yet it would soon enough prove to be so much more meaningful than that.
Peter and Mary Jane spent the next decade in an often on-again-off-again relationship, which finally culminated in their marriage over twenty years after they first met. The couple certainly had plenty of marital struggles, from family tragedies to the strain of Peter's superhero career, and even being brainwashed to try and kill each other by Spider-Man's enemies. No matter what came their way, the two persevered for another two decades, all the way until the ill-received events of 2007's Amazing Spider-Man #545 by J. Michael Straczynski and Joe Quesada.
With Aunt May's life on the line, Mary Jane sealed a deal with Mephisto himself, exchanging her and Peter's marriage for May's life. As devastating as this was at the time on an individual level, it also effectively reshaped decades of history in the Marvel Universe. Peter and M.J.'s relationship retroactively came to an early end, and Harry Osborn had survived his own fateful encounter nearly fifteen years prior. On top of that, the fallout of Peter revealing himself to the world as Spider-Man during Civil War was reduced to nothing, as no one could recall who the wall-crawler was any longer.
Somehow, not even all of that was the full extent of Mephisto's dealings with Peter and Mary Jane, and it has only been recently revealed precisely what the demonic villain was truly after. Aunt May wasn't the only May Parker whose life was on the line that day, something Peter and M.J. realized to their horror upon seeing the visage of the daughter they would never have. That May Parker, it turns out, is the one who is destined to unseat Mephisto from his throne sometime in the future. As seen in Nick Spencer and Christos Gage's massively oversized Amazing Spider-Man #74, there will come a time when Mephisto defeats every hero in the world to finally claim it as his own. When that time comes, so will his own defeat at the hands of Spider-Girl, and he is willing to go to any and every length imaginable to stop that from happening.
They might be iconic to the point of having become their own trope, but there is no denying just how important Peter and Mary Jane's relationship has been in the grander scheme of things. There just isn't any other couple that has been through what they have. Wanda and Vision have dealt with the devil and warped reality around themselves, yet there is no other romance that has literally changed the course of history, let alone both ways, like Peter and M.J. The fact that they hold such a key position in the Marvel Universe is already astounding, but the way they have always managed to pull through everything that position entails together makes them genuinely perfect for it.