Ugh, I'm so annoyed with myself, I accidentally deleted my frikkin draft instead of posting. So here we go again, and it's worse than my original @ringnis
TLDR #1; Daddy Cid and that sinful voice. Also, angst.
Longer answer (and possibly spoilers, and a lot of me rambling);
I think the dynamics and parallels between them are fascinating. Former high-society crushed into rogue soldiers, one by choice and one by fate. Everything after this is my own romanticized view, so…yeah, brace yourself and let me live.
In the beginning, Cid hadn't expected Clive to stay, he expected to give a young man a landing pad from escaping life and death as a disposable soldier. Personally, I think he drew parallels to his own daughter, Mid, who is about the same age Clive was when he was ripped away from everything he knew. What would he, as a father, have hoped for Mid, if she'd been thrown into the same situation?
But I don't think he meant to get attached, didn't expect Clive to stay, or to let his walls down and become the person he was turning into. Especially after Jill, he expected Clive to take the girl and leave, maybe take back the duchy, maybe just vanish into a normal life.
But Clive stayed, and more importantly, saw Cid for the broken man he was. Tried to take some of the burdens Cid recklessly threw himself into, not realizing he was just doing the same thing to himself.
Cid knows he's got a time limit, knows there's age and wisdom and worlds between them. He also acknowledges Clive is beautiful/pretty, but the angst in him trying to cut ties with those thoughts is so, so sweet to think about.
Cid saw the risks of destroying the crystal in ways I don't think Clive did. He didn't need to fully summon Ramuh, he could have just primed. But he made himself a large target, just in case. He knew who Ultima was, knew the Mother Crystals were draining the land dry, probably knew Ultima wasn't going to respond kindly to the destruction of one. Who knows what else he knew that he never got to say?
Another thing about their relationship is that Cid just accepts he's not the hero of the story? He sees Clive and is like, “Well, I may run the Hideaway, but this kid could rule the world.” He's been so important to so many people for so long, and then this guy who has been missing/presumed dead shows up in a 2-for-1 special and Cid is eventually like…finally. But it's not like he just rolls over. He makes Clive earn his trust, while Clive also endears himself to the people he's now decided to protect. Just like Clive proves himself to Cid's contacts later on, Cid makes him prove himself from the get-go. Hell, he doesn't reveal he's a Dominant until Clive shows he can carry a fight on his own.
“For so long, I thought I had all the answers. But then, I met you.”
Cid had been chasing death for so long, he had lost sight of what he'd really been fighting for. In the end, he'd been fighting for people to choose how they die, and forgot that before that, people should be able to choose how to live. Somewhere along the way, between arriving in Valisthea, becoming a Dominant, being Barnabas’ right hand man, leaving that life to make a better one, he forgot the reason he kept moving on. He forgot the reason he kept moving was to keep living. To be human, and alive.
And Clive gives that back to him.
TLDR #2; I just think they're neat. And I'm probably reading way more into it than I should. And I have way more to say but this has been in my drafts for way too long.