Cal Kestis was never made to fit.
As a Youngling, he learned his head is not always occupied by his thoughts alone. Echoes from unsuspecting nooks and crannies (and war) overload his brain, baring to him everything they once were, and forcing his mind to compute emotions too strong, too heavy. He had desperately wished, at the time, that it was his own feelings that were too big for his body.
After his Master dies, his lightsaber is twice the size of his own. It hangs heavy on his waist, bruising the sides of his thigh. It's foreign, unsuitable, a tragic reminder that drags his weight down yet he finds himself clinging to it like a child during the coldest nights on Bracca. No matter how many times his palms encircle the hilt, it would never fit the way it should.
His first poncho was five sizes too big. Prauf, like every other Scrapper, was living hand to mouth. "You'll grow into it" he insisted, a quiet muffled chuckle betraying his amusement as the heavy material hovered by his ankles. Cal is thirteen and his face itches from the cold, but the poncho is warm and it reminds him distantly of home. Cal never grew as big as Prauf, and the poncho still hangs past his shoulders, a few sizes too big.
Cal is seventeen and the names of a thousand Force Sensitives rests in his palm. He's seventeen, and the future of his kind is compacted into a single Holocron stained by bloodshed. His gut twists and turns with uncertainty and fevor and deep fatigue from the lengthy chase and almost getting his insides boiled, and he desperately wants to reach out snd grab that opportunity for a future. But Cal is seventeen, and can give nothing more to these children than their freedom. He's seventeen and he is unfit to guide the new Order, and it gnaws at him.
He's seventeen and he doesn't fit into this found family who place their needs over the Fight. So he leaves to find a place where he could fit as if being one of the last of his kind would allow him such mercy.
He's twenty-two and his emotions eventually settle as the sounds of battle become white noise and bodies become numbers. He is angry and betrayed, and loathing himself and losing himself, but the need to Fight thrums like electricity under his skin. He's twenty-two and he no longer fits into the mold of the old Jedi Order. He is not them, something in between.
Something that could never fit, but Cal Kestis was never made to, anyway.