He is the son of flower coordinator Makiko Katahira, who received bad press due to her son's actions. Obtaining the IceAge Memory to become the IceAge Dopant, Kiyoshi uses it to attack anyone who makes him mad such as Shotaro when he unintentionally shoved Kiyoshi out of the way while looking for Makiko.
After his clone is destroyed by Accel's Accel Glanzer Maximum Drive, believing the Dopant to be the one he is looking for, Kiyoshi runs into his mother as she takes the Gaia Memory from him to take the blame for the attack.
However, Shotaro uncovers the truth as IceAge Dopant is defeated by Accel's Dynamic Ace Maximum Drive and Ryu Terui arrests Kiyoshi instead of killing him in revenge, only to learn that Kiyoshi is not his target when he discovers that he possesses the IceAge Memory and not the W Memory. Up until this time, the IceAge Dopant is only referred to as the icy Dopant.
- Height: 260 cm
- Weight: 132 kg
As the IceAge Dopant, he has the ability to make absolute zero ice and use it in any fashion, from attacks to clones.