The dam begins to crack. Water begins seeping down its face. The two look at the impending disaster, then at each other. Suddenly, the boy springs into the air, picking up huge boulders and dropping them in front of the dam. The girl runs faster than can be seen, scooping up huge armloads of mud and packing them into the cracks between the boulders and then breathing on them to dry them into cement. The supporting structure being completed, the boy lands next to the girl, who smiles at him. He tosses a giant chunk of log to her, which she deftly catches and tosses onto the top of the new dam. An alliance has been formed.
In the next scene, they are living together. Not in a romantic sense, but more like roommates who work from home. Each has a personal staff of butlers, maids and assistants who keep them tidy, well-fed and informed. In one scene, we see them bathing together in the Super Tub. It can only be entered by swimming through a doorway under the surface of the water, and when UltraMegaBoy/Girl pop up on the inside of the Bath-O-Sphere (differing from a bathysphere in that the water's on the inside). There is a radio tuned to the police frequency so that at no time are they out of touch. And, since this has the look and feel of a 50's TV show, not only are the bathers wearing bathing suits, but the tub itself is divided down the middle by a wall - his side and her side. We're talking chaste.
So, off-camera they're saving the world and fighting crime and wearing spandex, but they're also getting older. Now they're in their mid-20's. All the while, UltraMegaBoy has been acting gallantly toward UltraMegaGirl, protective and chivalrous, but she has shown no interest in him. One night, though, we see UltraMegaBoy at dinner in a fancy restaurant with a woman, and she's NOT UltraMegaGirl. He's plainly smitten, so when UltraMegaGirl and her retinue walk in, he looks like he's been caught and he knows it. UltraMegaGirl and her entourage walk up and make the usual courtesies. "We didn't know you'd be here!" "So nice to see you."
He introduces the woman, who demurely greets the other party, her awkwardness plain. She knows her position, and it's not #1.
UltraMegaGirl is the kind of gracious that indifference affords one. She introduces her guests one at a time, saving the tall man at the back for last.
"And I'd like you to meet my husband."
UltraMegaMan may never recover.