Yoki

Yoki was the Pirate captain of the Rumba Pirates who brought Laboon to Reverse Mountain fifty years ago from the West Blue, he shook hands with Crocus. He and his crew were looking forward to exploring the Grand Line, but were saddened they had to leave Laboon behind because of how dangerous the Grand Line is. They promised to return someday in two to three years and take Laboon back with them.

Yoki and his crew however didn't returned. They were attacked in the Florian Triangle and all of them were killed. A few years later, seeing as Yoki didn't returned, Crocus theorized about what happened to the captain and the crew. Crocus theorized that Yoki and his crew got scared of what they had seen and endured and left the Grand Line in desperation after only going a short distance into it. They left via the Calm Belt and the most obivous outcome was death for the entire crew.

The Straw Hats told Laboon that their crew may be still alive somewhere, hoping it would keep his spirit of seeing them return alive high. However it was not enough to convince the whale. Though it has been fifty years since then, only one of Yoki's crew however remained after the attack, Brook.

Anime and Manga Differences
In the manga, Yoki's face is slightly unclear. In the anime, his face is clearly seen in the flashback. Also, Yoki is seen wearing what appears to be a cowboy hat in the manga while in the anime, he is seen wearing a typical tricone.