Bogart is the direct subordinate of Monkey D. Garp.
Bogart is a supporting character from the One Piece series that was created by Eiichiro Oda, the series writer and artist. The series first began serialization in Shueisha's Weekly Shōnen Jump on August 4, 1997. His first appearance was in the later on the splash pages of Coby's Dream Story.
He first appeared in the splash page on One Piece Volume 11, CH. 92 "Paradise".
Bogart appears in the very end of the Whiskey Peak Arc. He assists Vice-Admiral Monkey D. Garp in training Coby and Helmeppo. It is from training them that we find out his skils as a swordsman for he managed to cut the guns Coby held without harming Coby at all.
Bogart is seen present with Garp when he goes to see Garp's grandson, Monkey D. Luffy. Garp mentions that Coby and Helmeppo are his two strongest students. This could mean that they have surpassed Bogart; unless, Garp considers Bogart to be a subordinate only, not a student.