The Diamond Trio is a group of three friends, Alex Aria, who is the only female of the group she has short light brown hair and dark blue eyes, always wears glasses and often seen wearing her signature cap and is the girlfriend of Koby and cousin of Daniel Shirona, Koby, who is a marine of the grandline and has short pink hair and is the boyfriend of Alex Aria, and finally Rohan Kishibe the famous manga artist of Morioh and the best friend of Alex Aria and Koby

Alex Aria: Hey there, I am Alex Aria, but you can just call me Alex. I am the only girl of the friend group. I am pretty much a tomboy and is the girlfriend of Koby and the cousin of Daniel Shirona and best friend of Rohan Kishibe

Koby: I am Koby, a marine of the grand line, I am the boyfriend of Alex and the best friend of Rohan Kishibe. I'll do anything for both of them, and I will always keep them both safe and will always protect them both

Rohan Kishibe: And I am Rohan Kishibe. I am Morioh's famous manga artist and the best friend of Koby and Alex Aria. We all get along very nicely