|Title||Grandson of Ketouin Conglomerate's Current Head|
|Family||Hatakiyo Ketouin (Grandfather)|
Yuika Ketouin (Older twin sister)
Hiroyuki Ketouin (祁答院浩之 Ketouin Hiroyuki) is a character featured in Danganronpa: Togami. He's the grandson of the Ketouin Conglomerate's current head, Hatakiyo Ketouin. He's the twin brother of Yuika Ketouin.
Hiroyuki at first appears to be a very relaxed and playful, but he is also vile. He says himself that he can be a prankster.
Volume 1 - Multiple Counts of Attempted World Domination
Chapter 1 - Byakuya-sama is God
Hiroyuki first appeared when he and his twin sister, Yuika, came with their Mercedes-Benz to save Byakuya Togami and Shinobu Togami from Sonia Nevermind soldiers' attack. In turn, Hiroyuki wanted the information and Secret to Togami Family's Prosperity after they arrived at Hiroyuki's hideout. As he drives, drenched in beer, Hiroyuki suddenly crashed into the Ultimate Martial Artist, Sakura Ogami. Using a technique called Shukuchi, Sakura was sent by Hope's Peak Academy to capture Byakuya, whom they mistakenly confused as the person who broadcasted the World Domination Proclamation. Troubled when he attempted to escape Sakura, Hiroyuki activated his Mercedes' jet engine and eventually escaped the powerful Sakura and soon arrived at the center of Prague where the people demonstrated, protested the World Domination Proclamation that could disturbed the peace.
As Hiroyuki and the others arrive at the demonstration location, one of his friends, Taeko Kanai reported back to him after she chased Sonia's crew. Due to Taeko's abruptness, the demonstration spotted them and begin to surround them, giving no escape route.
Later, Sonia reappeared with her armored car in a pincher attack along with Kazuichi Soda's flying machine gun to destroy Byakuya, who was inside Hiroyuki's Mercedes. Hiroyuki and the others eventually managed to escape after Byakuya learned and threw his old glasses that had been set with a transmitter to track him down.
Hiroyuki and the others eventually escaped the murderous events in the center of Prague and arrived in Škoda Auto factory that belonged to Ketouin Conglomerate.
- “What an honor. I'm Hiroyuki, the grandson of the Ketouin Conglomerate's current head, Hatakiyo Ketouin.”
- “I'm so weak to the cute ones. I like sticking insect pins in their arms and necks.”
- “I'm real bad at being the bad guy.”
- “You're acting pretty high and mighty for someone who's running away in nothing but a towel. Is that confidence really justified?” (to Byakuya Togami)