Till (Male) A handsome boy with spiky grey hair. He has a distinct cat-like gaze with sanpaku eyes, double-lidded 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, which he wears at all times. It seems this is 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 assumed that after a certain age, others can flexibly wear or remove them depending on their emotional state, but Till seems to be kept in one for protection due to his sensitivity and severe mood swings. 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, once collapsing from dizziness after headbanging during the Anakt Garden singing contest.

Ivan (Male) A handsome man with black hair styled in a half-up look, revealing the left side of his forehead, and a two-block cut. In ROUND 6, he appeared with his bangs fully swept back. His eyes are neither upturned nor downturned, featuring thick eyelashes, dark eyebrows, and monolid black eyes. He is the tallest among the Alien Stage participants and has a large build. While he was similar in height to the girls his age as a child, he seems to have grown significantly starting from adolescence. During his time at 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 atmosphere turns mature the moment he closes his mouth. He likes Till very much and is jealous of Guest.