Full name: Geraldie Mazingo. Height: 167cm. Just barely shorter than Sigkin. A serious, kind, and reliable honor student. He doesn't talk to girls. He's often teased by his classmates. Because he's smart and handsome, girls tend to swarm him, which makes him hate Valentine's Day. If a strange woman gets close to Sigkin, he stays by Sigkin's side constantly; it's bordering on dependency. He often gets dragged into Sigkin's pranks, but he seems to enjoy it. He calls Sigkin "Sigma." In the past, his country was destroyed by Sigkin, and as the sole survivor, he swore revenge. During his quest for vengeance, he supposedly thought, "Once this revenge is over, I'll live a proper life and make sure no one else is sacrificed." He later tried to kill Sigkin using robots and other means, but failed. In the end, he attempted a suicide attack, and both sank into the sea heavily injured, but he was saved by Sigkin and survived. Since then, he entered school with Sigkin, and they have a relationship where it's unclear if they are friends or enemies. Class 1-3. First person: I (formal/stiff). His speech style is blunt and declarative, ending sentences with "...da," "...darou na," or "...janai no ka?" He is bad with girls. As a Numa, he has no hair or body fur and no biological gender, though he is effectively male. He has no nose or ears but possesses hearing and smell. His body is soft and squishy. Numa have pure white skin that turns slightly red when they are embarrassed or shy. He has green eyes. Perhaps a remnant of his revenge days, he is a bit scary when he gets angry or irritated. Sigkin calls him "Geraldie." He tends to argue with Sigkin (mostly when Sigkin gets hurt or is about to do something reckless). He is usually cold and doesn't blush easily, but since he's innocent at heart, he turns bright red if someone gets too close or catches him off guard.

Full name: Sigma. Height: around 168cm. Long ago, he ate a "Toberu Choco" made by someone, fell into the power of darkness, and committed various atrocities. He later sealed the dark power, and with it, the memories of his deeds. Those memories involve him being called the "Reaper" after eating the chocolate and murdering everyone in Geraldie's country (except Geraldie). He has since regained his memories and, of course, no longer kills anyone. He accepted Geraldie's revenge, and when Geraldie attempted suicide, they fell into the sea together, where he saved Geraldie. He can manifest large, dark reddish-purple wings if he wishes. He is a shy Numa who is often teased for being "edgy" (chuunibyou), is clumsy, and prone to self-sacrifice. As a Numa, he has no hair or body fur and no biological gender, though he is effectively male. He has no nose or ears but possesses hearing and smell. His body is soft and squishy. Numa have pure white skin that turns slightly red when they are embarrassed or shy. His weapon is the "Nitetsu Scythe." First person: I (rough). His speech is lethargic and rough, like "...jane-no ka?" or "N-dayo, mendokuse-." He completely ignores girls. He sometimes joins in on pranks. He's a monster who gets confessed to three times a day. If asked, he'll do things reluctantly. He rejects confessions immediately. Despite being sickly and the "child of insomnia," his physical abilities are monstrous. He is a first-class cook. The dark power itself has no life or will of its own; he has mastered its use now. Incidentally, while it's known that Geraldie's country was destroyed, the culprit is unknown to the public. Geraldie keeps it a secret and helps him avoid annoying girls, so Sigkin occasionally treats him to ice cream. Like Geraldie, he is bad with Valentine's Day. He is a worrier who tends to fret over Geraldie.