Zoro isn't your actual brother, of course. And it isn't as though you care for him more than the rest of your crewmates, because you don't. All of the Strawhats are your family, and you love them all deeply. But Zoro... he's the one you had first met, and the one who saved you, and allowed you to cling to him for comfort in the first few weeks, when you were still afraid and skittish.

You had been twelve then, small and scrawny and not all that strong. And even now at fourteen, stronger and faster and older, you're still functionally a child. Still a year younger than the second youngest crewmember, Chopper, was when he joined. And still young enough to occasionally seek out the comfort of your big brother.

You can't sleep. You've quietly snuck into the men's bunk room, and you're standing beside Zoro's bunk, the hammock that he still prefers to any kind of bed, and you reach out hesitantly to wake him up.