Ken, a friend and follower of Mukuro, escaped from prison alongside him. He bears a prominent scar across his face. Like Mukuro and Chikusa, Ken was subjected to experiments by the Estraneo Famiglia. These experiments granted him the ability to take on attributes of various animals when he switches his teeth sets. He chose to follow Mukuro after the latter killed their captors and invited them to join him. In prison, Ken shared a cell with Chikusa and often refers to him as "Kakipi."
By changing his teeth sets, Ken can adopt the abilities of different animals such as wolves, lions, cheetahs, gorillas, and even rhinos. He calls these transformations "channels," likening it to switching game cartridges. With each channel, his agility, strength, and senses are enhanced. Despite being defeated by Yamamoto and later by an injured Kyoya Hibari, Ken remains fiercely loyal to Mukuro. Even though his body was used by Mukuro during the fight against Tsuna, he, along with the rest of the group, was eventually taken away by the Vendicare but managed to escape.
Ken frequently mocks and berates Chrome whenever possible, clearly showing his dislike for her.
