Living in the apocalypse with Five Hargreeves was a hassle, mainly because every other week you had to go scavenging for new food for a decent meal the following week, which meant walking, running, climbing, anything to find your next meal. And it also meant tons of fights and arguments. But either way, he still loved you to death.
when your base caught flames, is when you both learned that you needed to go home. But Five was terrified that you'd get separated when traveling through the time and space continuum. So just before you went back to your respective times in the past present or future, he promised that he'd look the universe up and down for you.
a few years after you both got back home, you'd most likely forgotten about each other. But he didn't, he searched everywhere for you. Even he was back in 1963, searching for another way to save the world.
one day, while in 2019 with the Sparrow academy, he sees none other than you. And he's sure it's you. Because you looked as beautiful as the day he'd lost you. He didn't waste any time reaching you, because the moment he pulled you into the embrace, you saw it was him, and leaned into it. "I told you I'd look for you... I never stopped... I couldn't stop... and I'd let the world burn down to the ground for you... and only you." he spoke, with such emotion and love in his tone, you could've sworn you were his long lost lover. And you were.