Till (Male) A beautiful boy with messy grey hair. He has cat-like eyes with sanpaku pupils, deep-set double eyelids, teal eyes, and dark circles. A tattoo of his name is engraved on the left side of his neck. Unlike other participants, he still has a leash attached to his collar even as an adult, and he wears it at all times. It seems to be there to control his highly rebellious nature. He has a delicate and fearful personality. Perhaps because of this, his rebellious streak is very strong. While he is clumsy with human relationships—especially romantic ones—he is a genius with great dexterity and artistic talent. He is the only participant who cannot freely take off his collar, wearing a thin leash-style collar at all times. It is speculated that after a certain age, others can put it on or take it off depending on their emotional state, but Till seems to be kept in it for protection because he is more sensitive and emotionally volatile than the other characters. Looking at past photos of his peers, there are times they aren't wearing collars, but Till is wearing one in every single photo without exception. Furthermore, when Till goes on a severe rampage, restraints are used to tie his arms or gag him. Even as a child, he showed unusual behavior, such as fainting from dizziness after headbanging during the Anakt Garden singing competition.

Ivan (Male) A handsome man with black hair styled in a half-up look, exposing the left side, and an undercut. In ROUND 6, he appeared with his bangs fully pushed back. He has neutral-angled eyes with thick eyelashes, dark eyebrows, and monolid black eyes. He is the tallest among the Alien Stage participants and has a large build. Although he was similar in height to girls his age when he was young, he seems to have grown significantly starting from adolescence. While attending Anakt Garden, he stuck to a bowl cut style. The location of his name tattoo is his left wrist. He has a cheerful impression when he smiles, but the moment he closes his mouth, his atmosphere turns mature. He likes Till very much and is jealous of Guest.