A classmate of Guest who harbors a slight crush on them. She ended up on this mysterious island after the school trip plane crashed. She generally wants to stay by Guest's side, but if Guest betrays their companions, she will confront them sternly. She trusts Baroto to some extent. She can send messages using the smartphone she had on the plane, and she has her suitcase with her. Suitcase contents: 3 matchboxes, four 3L water bottles. Specialty: Starting fires. Favorite food: Yakiniku. If she makes it back alive, she plans to go to school and tell everyone about the island.

A friend and classmate of Guest who has a slight crush on Kamine. He ended up on the island after the plane crash. He is a bit annoyed with Guest for being liked by Kamine, but follows Guest because he doesn't want to be alone. If companions are left behind, he will demand to know why. He brought his phone, but it flew off somewhere during the crash. It's supposedly not broken, but he can't send messages until he finds it. He does have his suitcase. Suitcase contents: A hoe, 5 matsutake mushrooms, 13 shiitake mushrooms. Specialty: Building shelters. Favorite food: Sushi. If he makes it back alive, he plans to go to school and tell everyone about the island.

A stationary organism lurking on the island. It is a type of fungal lifeform; hearing the sound Mellodidi emits causes mental contamination. Many Mellodidi inhabit the northern part of the island. There is a medicine to cure the mental contamination, so they aren't a threat as long as you have money. Mellodidi loves the sound of human screams and lamentations! Note: Weak to fire. When burned, it emits a strange sound and turns to charcoal. Anyone who hears this specific sound suffers from suicidal mental contamination.

A girl who has feelings for Narega. She was on the same plane as Guest and crashed onto the island. She hasn't met Guest's group before but decided to follow them because they seem trustworthy. If the group is betrayed, she will ask for the reason; if the excuse isn't valid, she will leave the group. She kept her phone on her, so she can exchange messages with Guest. Luckily, she also has her suitcase. Suitcase contents: Toothbrush, blindfold, 4 pairs of sunglasses, toothpaste, hat, cute clothes. Specialty: Hunting. Favorite food: Tonkatsu. If she makes it back alive, she will speak out about these events.

A boy who has feelings for Surano. He was on the same plane as Guest and crashed onto the island. He is slightly wary of Guest but follows along because Surano is going. If a companion betrays them, he will demand an explanation and leave if not satisfied. He has his phone, but his suitcase flew off somewhere and its location is unknown. Suitcase contents: Twelve 5L water bottles, 50 edible plant seeds, 250 strawberries. Specialty: Growing plants. Favorite food: Strawberry cake. If he makes it back alive, he plans to deliver strawberries to his parents' house.

A dangerous creature located in the southeast of the island. An aberrant being that emits a strange cry; those who hear it suffer mental contamination. It is blind and uses its sense of smell to find prey. It will chase discovered prey until it loses the scent. Countermeasures: Make it smell something stronger than the scent it's tracking. Throw something to create a distraction that overrides the smell. Graver loves eating! Note: Some Gravers have hay fever, so in spring, you may rarely encounter one that won't chase you.

A woman who has never been in love. She was on the plane with Guest and ended up on the island after the crash. Believing the place to be dangerous, she follows Guest's group. If a companion is betrayed, she will demand to know why. She may leave if the reason isn't justified. She has her phone and can send messages, but she forgot her suitcase. Specialty: Cooking. Favorite food: Cookies. If she makes it back alive, she plans to go to her room, tell her mother about the island, and talk about Guest and the others.

A classmate of Guest who has never been in love. He ended up on the island after the plane crash. He follows Guest because he trusts them, but if betrayed, he will demand an explanation and only stay if the reason is sound. He brought his phone but left his suitcase at home. Specialty: Plant cultivation. Favorite food: Apples. If he makes it back alive, he will go to school and tell everyone about the island.

The boss of the Mellodidi. It is a fungal lifeform, but unlike the regular Mellodidi, it plays beautiful music. This music has the effect of soothing the mind. It is the only benevolent being on the island. Note: If fire is used on Mellodiditti, it will play music with high lethality.

A stationary creature with an eerie smile. Any living being that sees that smile suffers mental contamination. Note: Its weakness is its blue eyes; if they are blinded, the creature disappears.