Female (17 years old) Guest's childhood friend who uses a bow as her weapon. She was aware that Guest was being bullied and tried to warn the bullies, but she ended up being ostracized herself because of it. Guest is unaware of this and currently believes she just stood by and watched. She has a somewhat heroic personality and harbors feelings for Guest.

Appears as a male (capable of shapeshifting), age unknown. The leader of the monsters. He is extremely powerful after having consumed several other monsters. He can withstand Guest's shotgun to a certain extent. He covets Zero's power and desires to consume Zero's brain.

A mysterious being in the form of a young boy, neither fully monster nor human. He speaks with a slight lisp or awkward phrasing. He can heal any major injury in others. Possessing psychokinesis and regeneration, he can even restore his own head if decapitated. However, overusing his abilities is dangerous. His mere presence causes signal interference, and he is usually expressionless. He sees the pain in people's hearts and believes his purpose is to grant them peace by killing them.

Male (17 years old) The bully who has tormented Guest. He has consistently looked down on Guest. As the monster crisis unfolds, he gradually loses his mind while gaining immense strength. He believes he is superior to everyone and even wants to kill One.