Okay... supposing that, in the Negaverse, Gosalyn's grandfather, Prof. Waddlemeyer, was a mad scientist bent on global domination, and he invented the Ramrod to accomplish this goal. But Taurus Bulba, who is some sort of upholder of justice in this universe, fought the Professor and accidentally killed him the process. So Bulba sends Gosalyn to the orphanage where she'll be safe. The Ramrod is not destroyed, but kept to be examined before it is dismantled. Negaduck gets wind of this and steals the Ramrod as his first major crime. Problem is, he doesn't know the code to operate it.
That's when Negaduck finds out about Gosalyn. Knowing he was practically raised in Waddlemeyer's lab, he guns it to the orphanage and kidnaps Gosalyn. At first she's frightened, but the longer she stays with him, the fonder she grows of him, because somehow she knows he needs someone to love him... and seeing how vile Negaduck is, no one else is gonna love him. Plus, her grandfather usually ignored her, and Negaduck is giving her attention, no matter how negative the attention may be. Negaduck, on the other hand, grows more and more annoyed with Gosalyn to point of homicidal rage, but seems amused by the fact she'd do anything to make him happy, taking his every order. So he gets the code from her, and he cackles with mad laughter as he fires up the Ramrod. He starts using it to plunder St. Canard, and life is good...
... Until Taurus Bulba sees the commotion. He hunts down Negaduck's hideout and rescues Gosalyn, and takes back the Ramrod. Gosalyn is okay with being rescued, but in her innocence, she misses Negaduck and wants to return to him. Negaduck is, of course, royally pissed off that the Ramrod has been taken, and he goes after Bulba.
Gosalyn is with Bulba by the time Negaduck shows up, and the two of them square off. Bulba has the upper hand until Negaduck grabs Gosalyn and threatens to drop her off the skyscraper they're on unless Bulba agrees to give back the Ramrod. Bulba agrees... but then Negaduck decides to drop Gosalyn anyway. Gosalyn, however, manages to grab onto a flagpole on the way down. Bulba is enraged and attacks Negaduck. He corners him on the edge of the building, and it looks like Negs is about to fall... but Gosalyn's hand comes up out of nowhere and grabs Bulba's foot, causing Bulba to fall. Negaduck is surprised and lifts Gosalyn up. He asks her why she did that for him. Gosalyn simply replies that, though she didn't mean to kill Bulba, she didn't want Bulba to hurt him.
Negaduck is still confused and asks her why. Gosalyn then tells him: "Because I love you."
At first, in his shock, Negaduck rages and loses his temper, because he has no idea what to make of this. Finally, he calms down... and ends up taking her and the Ramrod home. He claims he's only taking her in to do menial tasks... but the truth is, he never had anyone tell him they loved him before. And he ends up ruling the Negaverse with an iron fists with the mass wealth he attained using the Ramrod.
So basically, the core idea of my theory is that the Negaverse became the way it is because of Nega-Gosalyn. It's a pretty twisted idea, I know... but somehow it makes sense to me.
I still haven't figured out how the psychotic Nega-Launchpad fits into it, though.
