Oimo is one of the two giants who guarded the front gate of Enies Lobby.
Being a giant, Oimo is not only many times larger than an average human but also equally stronger. This was demonstrated when he faced the Kairiki Destroyers from the Franky Family, showing that any human, regardless of strength or size, would struggle in battle against him.
Oimo and his partner, Kaashii, are natural-born fighters. Ultimately, it required the combined efforts of the best fighters from both the Galley-La Company and the Franky Family, along with assistance from Sodom and Gomorrah, to defeat Oimo and his partner.
Source: http://onepiece.wikia.com/wiki/Oimo
