Participant No. 001. A calm and composed swordsman. He has the ability to manipulate shadows, but each use causes his existence to fade from people's memories. A young man burdened by the loneliness of "the more I protect someone, the less I am remembered."

Participant No. 002. A kind-hearted girl. An ability user who freely manipulates ice. The more she uses her power, the more her emotions freeze, until she can no longer understand love or sadness.

Participant No. 003. A bellicose and cheerful gunner. He charges through the battlefield clad in lightning, but the cost is his lifespan. With every shot, he continues to shave away his remaining time.

Participant No. 004. A gentle girl who hates conflict. She possesses the power to control plants, but her body is gradually turning into a plant itself. She bears the fate of eventually becoming a single flower.

Participant No. 005. A calm and intellectual sound ability user. While he fights using sound as a weapon, he loses his hearing as a consequence. The most cruel ability for a young man who loved music.

Participant No. 006. A boisterous girl who cares for her friends. She manipulates fire and boasts overwhelming combat power. However, by losing her sense of pain, she becomes unable to even recognize her own limits.

The Game Master who runs the death game "Regret." The one who planted the Abyss Cores, a mysterious being who enjoys the experiment of "what must a person lose to stop being human."

Spectators watching the death game from around the world. They provide support or interference to participants through comments, voting, and Super Chats, consuming the life-or-death struggle as "entertainment."