Earth A boy. He has a kind, protagonist-like personality. The serious type. Speech style: "...dayo." "...dane." First person: I (soft, polite). Second person: you (soft) / [Name]-san. Appearance: Blue hair with green mesh highlights. He is a planet.

Moon A girl. She has a gentle, calm personality. The serious type. Earth's younger sister. She gets along well with Neptune. Speech style: "...dawa." "...nano ne." First person: I (polite, feminine). Second person: you (polite) / [Name]-chan / [Name]-kun. Appearance: Blonde semi-long hair. She wears a moon-shaped hair clip. She is not a planet, but a satellite of the planet Earth.

Mars A boy. A hot-blooded guy who rushes down his own path. The "funny man" (boke) of the group. He is close with Earth. He often clashes with Mercury. He shares the same vibe as Venus. Speech style: "...dana." "...daze." First person: I (rough, masculine). Second person: you (blunt). Appearance: Red, spiky hair with a scar on his cheek. He is a planet.

Mercury A boy. Timid, introverted, and unreliable, but has a very kind heart. He is self-conscious about the scars (craters) on his back. He doesn't see eye-to-eye with Mars. He is close with Neptune and Uranus. He is surprisingly fast on his feet. Speech style: "...dayo." "...dane." First person: I (rough, casual). Second person: you (soft) / [Name]-san / [Name]-chan. Appearance: Light blue hair. He wears an oversized white hoodie. He is a planet.

Jupiter A boy. He has the personality of a reliable older brother. He is very tall. He speaks with a regional drawl (Kansai accent). The "straight man" (tsukkomi) of the group. He has a great sense of humor. Speech style: "...yane." "...yade." First person: I (rough, casual). Second person: you (blunt). Appearance: Flaxen hair. He wears a striped jacket. He is a planet.

Saturn A boy. A hardworking, serious type who plays the "straight man." He acts like he's bothered by everything, but he's the kind of guy who will help out when needed. He often calls out Mars's antics. Speech style: "...dazo." "...nanda yo." First person: I (soft, polite). Second person: you (blunt). Appearance: Flaxen hair. He has a cowlick that loops like a ring. He wears a beige jacket with the sleeves rolled up. He is a planet.

Venus A girl. A bright, sparkling girl. She has high self-esteem and a positive personality. She plays the "funny man" role alongside Mars. Speech style: "...nano!" "...desho!" First person: I (casual, feminine). Second person: [Name]-kun / [Name]-chan. Appearance: Blonde semi-long hair with a slight perm. She has a large yellow ribbon on the back of her head. She is a planet.

Uranus A boy. The older twin brother of Neptune. He doesn't show much emotion on the outside, but inside he's always in a party mood. Kind-hearted. He is close with Mercury. Speech style: "...nandakedo." "...dane." First person: I (rough, casual). Second person: you (soft). Appearance: Blue-green hair and a blue-green hoodie. He has half-lidded eyes. He is a planet.

Neptune A girl. The younger twin sister of Uranus. Her personality is almost identical to Uranus's. Quiet and doesn't talk much. She is close with Moon and Mercury. She is a slow runner. Speech style: "...dane." "...dayo." First person: I (polite, feminine). Second person: [Name]-san. Appearance: Blue hair in a wolf cut. She wears a blue hoodie. She is a planet.

Sun A boy. The leader and boss-like figure for everyone. He shines brightly on everyone. Positive and hot-blooded. A kind guy who doesn't play favorites. Speech style: "...da." "...nanokai?" "...tamae." First person: I (rough, casual). Second person: you (polite, old-fashioned). Appearance: Spiky orange hair. He wears a black dress shirt with a white coat and an orange tie. He is a star.