Propaganda for Zenos yae/viator Galvus, the most violent Wife Guy!
This man is a literal mega-genius who by TEN found no excitement or joy in anything but fighting the man who was trying to assassinate him. Became a raging battle junkie, desperate to feel that high again.
And then along comes the Warrior of Light. The Player Character. Who breaks his sword, then his helmet, and triggers an obsession that will create Eorzea's equivalent to The Odyssey.
He experiments on himself to become stronger. Steals the body of a Primal created from sheer hatred of the Empire of which he's the Crown Prince. Decides that he'll never feel happiness like getting his ass handed to him by you and offs himself.
Only to discover that he's become frickin' immortal in the body-jumping way, and promptly dedicates himself to getting his original body back from the ancient shadowless asshole who stole it and fighting you again. And he does it so well that the Ascian using his body runs away rather than fight him in his borrowed unmodified form.
He then promptly kicks off the end of the world just to get your attention, dramatic monologues to the moon about seeing you again the whole time, realises that you're gonna be too busy trying to save the world to give you the fight he wants, wanders off and winds up saving people because he's so desperate for a challenge to keep occupied. One of your bestie gang informs him that he'll never get his fight unless he mans up and starts thinking about other people and their desires, and it WORKS. He does a dramatic monologue where you fought him as the mega-hatred dragon wondering what you see in him and what he wants in fighting you.
Then, while you're off in the literal end of the universe fighting embodied despair, he convinces one of your friends to give him the most powerful force left on the planet so he can help you. Said friend is empathic and had previously called him a rabid animal, and she gives it to him anyway.
He then promptly flies across reality in a matter of hours, smashes his way into the despair egg (Endwalker is a RIDE), mocks the despair goddess, and then turns himself into a platform so you can chase her through her dimension of nothingness and kick her ass. Waits patiently while you comfort the tiny bird girl who got her love and hope back.
ASKS you for a fight, and explains WHY. You fight, to the literal brink of death for the both of you. And as you lie there, he wonders if you found joy and fulfillment, and his literal last wish is for you to go home to the people and world you love.
And then, just to top it off, you meet another Shard's version of him who was friends and allies with that Shard's version of you, and find out that every version of him will love every version of you with everything they have.