Height: 184 cm

Isao Kondo is the Commander of the Shinsengumi. When not working, he is the stalker of Tae Shimura, earning him the nickname Gorilla-stalker. His superior is Katakuriko Matsudaira, a high-ranking government officer under direct control of the Bakufu. Even though the Shinsengumi are loyal to Kondo, he often has to use Vice Commander Toshiro Hijikata to settle them down (with harsh words or use of violence) before conducting a speech. Kondo is good friends with Toshiro and Sougo Okita, and if one of them ever strayed, then the other two would punch him back to where he belongs, as Kondo once told Sougo. Sougo also often remarks that Kondo's nice-guy attitude is also his weakness as he never notices negative points about other people. In the Mutiny arc, he was described by Kamotaro Ito as honest, pure and unsullied. In the same arc, Toshiro described him as the soul of the Shinsengumi, and the rest of them being the sword that protects him. Toshiro also said that everybody joined the Shinsengumi so that they could be with Kondo, and that as long as he was there, the Shinsengumi would not be finished.

When Kondo once asked Tae Shimura whether she would still love her boyfriend if he had a hairy butt. She became the target of his stalking when she replied that she would love her boyfriend just as much, hairy butt and all. Being a stalker of Tae, Kondo is often seen getting beat up or threatened by her, as she highly disapproves of his stalking and affection towards her. In the Yagyuu arc, Kondo had his mind set on being Shinpachi Shimura's brother-in-law, even going as far as saying Shinpachi was the only one he could entrust the Shinsengumi to, much to Shinpachi's annoyance, answering that he doesn't give a damn about the Shinsengumi.

During his childhood, Kondo was a member of a dojo in Bushuu. There, he would soon meet Sougo and Toshiro, recruiting them both into his dojo. Kondo would later on take all the members with him and move from Bushuu to Edo in search for success, becoming what is now the Shinsengumi. Some characters in the series often call him "gorilla" due to his hirsute nature and although he is angered with this nickname, he sometimes uses the same word to identify himself. Kondo is loosely based on the historical Kondo Isami, famed for his role as commander of the Shinsengumi during the Bakumatsu period.