Uni

Ikkaku is a member of the Heart Pirates. His name was revealed in Volume 83's SBS.

Personality
Along with Ikkaku and Clione, Uni was against the idea of allying with the Straw Hat Pirates, thinking of their assistance as worthless.

Past
A month before Trafalgar Law formed an alliance with the Straw Hat Pirates, Uni and the other Heart Pirates were left on Zou under the watch of Nekomamushi. Uni, Ikkaku, and Clione were against forming the alliance, but were outvoted.

Zou Arc
Around a month and a week later, Law returned to Zou, and the Heart Pirates happily reunited with their captain when he came into the Whale Forest.

That night, the Heart Pirates briefly met Monkey D. Luffy for the first time before Law went to see the Straw Hats. The Guardians later threw a party for the Straw Hats that lasted throughout the night, which the Heart Pirates joined in.

The next day, the Heart Pirates, some of the Straw Hats, Kin'emon, Kanjuro, and Raizo departed Zou for Wano Country on the Polar Tang.

Trivia

 * Uni means "sea urchin" in Japanese, corresponding to the cold climate animal naming theme of the Heart Pirates.