Mr. 5 is the lowest-ranked Officer Agent in the Baroque Works along with his partner, Miss Valentines Day. Like most of the Baroque Works agents, he is extremely confident. He is especially devoted to his work, and believes that friendship is a sign of weakness. Mr. 5 has a five on his coat.

Mr. 5 has the power of the Bomu Bomu No Mi (Bomb Bomb Fruit in the English and Boom Boom Fruit in the English Manga) which allows him to turn any part of his body into a bomb, and renders all explosive based attacks useless against him. Mr. 5 and Miss Valentines Day first meet the Straw Hat Pirates at Whiskey Peak during the Whiskey Peak Arc, then later fight them at Little Garden, where they are defeated.