Iō has black eyes and brown hair covered by his forehead protector which he wears in a bandanna-style. He wears the standard attire of the Konoha-nin complete with flak jacket. While working on the Logistical Support and Medical Division compound he wears medical overalls to cover his attire.
Abilities
As a medical-nin, Iō first and foremost has excellent chakra control with which to perform delicate medical ninjutsu. Battle-wise, Iō is a competent shinobi and is capable of using Earth Releasenature transformation, making use of techniques such as the Earth Release: Flying Thrown Stones to bombard targets with, delivering devastating blows with each shard of stone. He also incorporated the use of sealing tags with his Earth Release techniques to create a makeshift method of sealing away reincarnated shinobi.
Part II
Shinobi World War Arc
During the Fourth Shinobi World War, Iō was assigned to the Logistic Support and medical Division. During a quell in the war, with heavy casualties coming into the compound, the KIA scroll was stolen Sukui assigned Iō along with Yokaze, Sakura Haruno, and Yūgao Uzuki to retrieve it as it contained the corpses of shinobi with kekkei genkai and other unique abilities sealed away in it. When the team caught up to the opposition, Iō fought alongside his comrades and was successful in sealing away both the Suna, and Kumo-nin. However, his confrontation with Hayate Gekkō ended with him being heavily wounded. Healed by Sakura, Iō was not able to continue on the mission and left the sealing of Hayate to his remaining comrades. Their mission ended in success with all three shinobi being sealed away successfully.