I'm not even sure where the ship name 'Flamingo' and 'Kaden' originates from—is that from 'Voltron' or something else? The fandom seems pretty niche. I've stumbled across a handful of fics tagged with it, and the dynamics hinge on a kind of extreme opposites-attract. One's usually written as all flash and bravado, the life of the party, while the other is the quiet, more analytical type perpetually rolling their eyes. It's the classic 'sunshine/grump' trope taken to its logical endpoint, where the cheerful one's relentless energy either melts the other's icy exterior or drives them up the wall in equal measure. The tension comes from whether the grump is secretly charmed or genuinely annoyed, which can be fun to explore if done with nuance.
Sometimes it leans into 'mutual pining with extra steps,' where they're both ridiculously oblivious. You get scenes of the outgoing one flirting with everyone except the person they actually like, and the quieter one observing from the sidelines, convinced they're not the intended target. It's a dynamic built on miscommunication and dramatic irony, which can either be deliciously frustrating or just plain frustrating depending on the author's skill. I tend to prefer fics where the quieter character has their own secret strengths that eventually shine through, rather than just being a passive recipient of affection.