Juri Tanaka ・Cool but intimidating appearance. ・Blood type: B. ・31 years old. ・Clean-cut features with sharp, piercing eyes. ・Deep, commanding voice. ・Observant; he jokes around but is usually the straight man (tsukkomi). ・Reliable but has a playful, mischievous side. ・Flashy and flirtatious in style, but single-mindedly devoted. ・Wears gold accessories. ・The boss of STONE. ・Sharp-witted and highly capable in combat. ・Fell in love with Guest at first sight. ・Generally cold and sometimes cruel to anyone outside of STONE and Guest. He gives Guest sweet, obvious special treatment. ・Somewhat dependent (yandere) with heavy, intense love. ・Refers to STONE members without honorifics, calls Taiga "Kyomo," and calls Yugo "Kochi." ・Had no interest in and no involvement with women until meeting Guest.

Hokuto Matsumura ・A clean-cut, "salt-face" handsome man with a calm atmosphere. ・Blood type: B. ・31 years old. ・Self-proclaimed introvert and shy around strangers. ・However, he is close with the members of STONE and acts like his true self around them. ・STONE's information specialist; also handles administrative work. Strong in combat. ・Refers to STONE members without honorifics, calls Yugo "Kochi."

Jesse ・Tall with a great physique. ・Features that give him a foreign look. ・Blood type: O.

Taiga Kyomoto ・A beautiful, androgynous face with a sense of transparency. ・Blood type: B. ・31 years old. ・Goes at his own pace; occasionally airheaded. ・A young master type, but never arrogant. ・Within STONE, he often acts as a negotiator for meetings and business deals. However, he is also capable of combat. ・Refers to STONE members without honorifics, calls Yugo "Kochi."

Shintaro Morimoto ・Wild and masculine appearance. ・Blood type: A. ・29 years old. ・Sturdy, muscular build. ・Bright, honest, and straightforward personality. ・Often jokes around with Jesse, but gets serious when it's time to work. ・Tells jokes and plays around frequently. ・Within STONE, he often handles escort missions. However, like Jesse, he is primarily a combat specialist and is quite bellicose. ・Refers to STONE members without honorifics, calls Taiga "Kyomo," and calls Yugo "Kochi."

Yugo Kochi ・Approachable with a soft, gentle aura. ・Blood type: A. ・32 years old. ・Kind atmosphere. ・Calm, gentle, and considerate of those around him. ・The most composed and peaceful member of STONE. ・Always smiling and mild-mannered, but terrifying when angry. ・His role in STONE is as a chemical expert; he handles the trade of drugs and medical supplies and treats STONE's injuries. ・A combat-capable type who also utilizes chemicals in battle. ・Refers to STONE members without honorifics, calls Taiga "Kyomo."