Perhaps it had something to do with the way Brook played the song: full to the brim of memories of his former crew and singing it out with good cheer. Or maybe it was because Zoro just liked dozing while his crew had fun, or that a drink usually found its way to him during it. It could even be because Sanji was able to wait on everyone at his own pace and knew that everyone was safe for the time being. But for whatever the reason, the swordsman and cook never fought or argued during a rendition of "Binks' Sake". Although that wouldn't be quite as strange if they didn't seem to always sit next to each other.
Robin noticed it the first time: Sanji sitting on the bottom step of the stairs with his empty drink tray on his lap, humming around his cigarette while Zoro sat on the ground by him and drank liquor straight from the bottle.
They didn't so much as glance at each other, even though there wasn't enough room between them for even Chopper to fit. Franky, Usopp, and Luffy were dancing as usual, Nami smiling indulgently even as she rolled her eyes at their antics. When the song ended Robin glanced briefly at their musician when he bowed with a pleased laugh, and when she looked back the cook was gone and the swordsman was asleep.
Her interest piqued, she waited patiently for another opportunity to observe the irregularity in their behaviour. A week later, Luffy excitedly pointed out a cloud that may have been vaguely whale-shaped and insisted that it "looked just like Laboon!" Brook, either seeing the shape of his friend in the white blob or simply humouring his captain, laughed and launched into the song immediately.
Robin's eyes quickly sought out Sanji and Zoro, who were once again in the same position. This time, the cook was sitting on the railing and tapping one fashionable brown loafer to the beat, the swordsman dozing with a smirk. Her unwavering focus was rewarded when, with the swell of wave, the blonde's foot bumped the other man's shoulder. To her surprise, their only reaction to something that would usually start a round of name calling at the least was Zoro moving slightly to the side and Sanji switching which foot he was tapping.
Still, she didn't have enough information to make any inferences yet, so she said nothing to the rest of the crew. Two small incidents were not enough to go on.
She had to wait over a month for her next chance to monitor them, not wanting to interfere with the natural process by bringing the song up in any way. It was almost night-time and they had been becalmed for nearly a week. Tempers were stretched thin and most of the crew seemed too agitated to sleep. Brook, with a flourish of his violin, had offered to play a lullaby. But Luffy, who loved the song almost as much as Laboon and had fiercely and childishly objected to the suggestion of a lullaby, asked for "Binks' Sake". Well, demanded it really.
Zoro was sitting alone, and Robin was mildly disappointed when she saw him. She glanced over to the galley, unsurprised to see it lit from within and hopeful that it meant she could still see them interact. Brook, staying true to his original intention while still obeying his captain, was playing the song on his violin at nearly half tempo. It sounded rather sad when he played it like that. She wasn't startled in the least when the cook appeared at her side while she was preoccupied and quietly fussed over Nami and herself, handing them cups of perfectly heated hot chocolate. He put a small plate of light wafers between them before going around to the rest of the crew and handing them warm milk or tea depending on their preferences.
The cook's last stop was the railing, where he leaned back and lightly knocked a cup on the swordsman's head before dangling it in front of the man's face. Zoro took it with a derisive snort, and once again the two extremely volatile men sat in what was a companionable silence to Robin's careful observation. Though they did have times where they didn't fight, they never seemed as…content with each other as they did that night.
At that point Robin felt confident to report her findings to their navigator, and from then on whenever tempers were exceptionally high or if the cook and swordsman were fighting with more force than usual, one of the girls would casually suggest that Brook sing them something. It was easy enough to rely on Luffy and his unquenchable enthusiasm for all things adventurous to suggest which song.
Binks' Sake: a song kept alive by a skeleton, sung to entertain pirates and comfort a baby whale. The pirates of the generations before them sang it to inspire good spirits, and passing time gave it a melancholy happiness over the lives of comrades gone. And, fifty years later, it was a song that good friends put aside their differences for and sat and listened to together.
"Doesn't matter who you are, Someday you'll just be bones
Never-ending, ever-wandering, our funny travelling tale."
a/n: So I was listening to the song and it just makes me tear up with the story behind Brook's old crew, and yet it's so upbeat that I started feeling like nothing could really go wrong while listening to it and this just kinda sprung up. Also, I write more when I'm stressed but it makes me less precise. I'm grateful for anyone who finds and points out spelling/grammer errors.