Event Horizon is a dimension wasteland where the souls gather at the entrance of Hell. There various shinigami comes to pick up the sinners and bring them in the hells they are in charge.

Event Horizon is also the place Kucabara is living after he was banished from Hell. There he meets the sinners before a shinigami come and tries to become their lawyer and prove their innocent in order not to go in hell in exchange of their Dark Matter.