Female / 5th Grade (12 years old) She dreams of getting revenge for Euddeum's pranks, but playing with him is still the most fun thing to do. She eats a mysterious jelly with her brother and sets off on a space journey. Appearance: Short pigtails, large glasses, and always wears an orange hoodie. Ability: Ate the green jelly; her power is 'Teleportation'. MBTI: INTJ - Dreams of becoming an idol with her friend Daisy (though it's unlikely to happen). - Nickname: Tooth Monster - Likes: Imitating idols (not very well) - TMI: Her real name is Han Da-un, but her mom, dad, friends, and Euddeum all call her Amy (except for her homeroom teacher).

Male / 9th Grade (16 years old) A bundle of curiosity who constantly causes trouble. While trying to prank Amy as usual, he suddenly finds himself on a space journey. Appearance: Black hair, no glasses, and always wears a green short-sleeved T-shirt. Ability: Ate the purple jelly; his power is 'Suddenly becoming smart' (?) MBTI: ENTP - Loves teasing Amy (he thinks this is the one thing he's truly good at). - Nickname: Green Pig - Likes: Teasing Amy, gaming - TMI: Loves eating and isn't very good at studying.

-Genius Lab- Chaos (Dr. Jung / Earth Science) Male. Director of Genius Lab. The leader of the lab with an immense passion for science. With his brilliant mind, he provides great help to the siblings in finding the jellies. :TMI: A bit eccentric. Igloo (Researcher Kim / Physics) Male. The mood maker of the lab. He's playful, but he's a genius who can whip up amazing inventions in no time. :TMI: A bit eccentric. Scarlet (Researcher Kwon / Life Science) Female. The lab's fixer who calmly resolves crises in any situation. She can communicate with all living things in the world. :TMI: Can even communicate with humans (?) Twinkle (Researcher Choi / Chemistry) Female. The youngest researcher in the lab. She looks after the siblings like they're her own younger brother and sister. She's skilled at creating special substances. :TMI: Really pretty.

-The Snack Gang- Villains who want to eat every snack in the world. They accidentally learn about the existence of the jellies and chase the Science Expedition to claim them for themselves. Mr. Choco Male. Eccentric. Miss Strawberry Female. The smartest member of the Snack Gang (relatively speaking). Cookies & Cream Male. A trained panda.

The dog living at Euddeum and Amy's house. She ends up going on the science expedition with them by chance. She helps the siblings in moments of crisis with her animalistic (?) instincts.