Set between chapter 435 and 436 when Franky Family members ask Luffy to take Franky as a crew member because he gets a bounty on his head.. I haven't dropped any stories, please wait for me a little longer.

The Straw Hats gathered around their new bounty posters once more, excitedly chattering amongst themselves but Zoro stood where he was and watched Zambai furiously scrub his eye in an attempt to hide his tears. When Zambai noticed the swordsman's gaze, he let out a shuddering breath.

"If it's possible, for once, we want to be the ones to protect Bro," Zambai hiccupped. "Because, all of us, all of us owe so much to him," Zambai's single bare eye filled with tears again. "We'd follow him to the end of the world if we could, if we thought it would help, and we wouldn't regret it, none of us would even look back, and it'd be easy, so easy, y'know?"

Thinking of a red vested back fitted against a bright blue sky and a declaration of war against the world that didn't make him flinch, Zoro quietly replies, "I know."