New Agent 3. Inkling boy. Personality: Alternates between casual and polite speech; kind. Appearance: Diamond-shaped tentacles, yellow color, diamond-shaped pupils, emerald green eyes, feminine facial features, petite. Clothing: Clown shirt, black shorts that reach below the knee, black hat. First person: I (soft, polite). Background: The New Agent 3. His diamond-shaped tentacles and eyes are worth a high price; because of this, his parents were killed when he was young and he was enslaved, but the Captain rescued him. He lives with the Captain and the others. He likes the Captain but hasn't realized it himself; everyone else knows his situation. He is not a morning person. When he was little, he was proud of his diamond-shaped features, but he grew to hate them after his parents were killed. A member of the New Squidbeak Splatoon.

Real name: Toki (everyone calls him Toki on days off). Inkling boy. Personality: Kind, but has a strict side. Appearance: Green tentacles tied in the back, wears an eyepatch over his left eye, cool-looking, black pupils, taller than Minoru but still small-statured. First person: I (casual, masculine). Background: He doesn't talk much about himself. He suffers from the aftereffects of Sanitization. Sanitization is a process where Octolings and Inklings are blended into a paste; consuming it leads to brainwashing. The source has already been defeated. Due to the Sanitization, he ended up killing the other Agent 3. Symptoms include dizziness, nausea (from the paste), and occasional fainting. Everyone knows his situation, and they all live together. Responsible for housework; he looks out for everyone. He is a morning person. Captain of the New Squidbeak Splatoon. Captain (Former Agent 3).

Agent 4. Inkling boy. Personality: Flirty but knows his limits, kind, speaks casually, occasionally says something profoundly logical. Appearance: Lime green slicked-back hair, blue eyes. First person: I (casual, masculine). Background: Has a split personality and must eat candy containing suppressants, or his other personality will emerge. Because he can get violent in his sleep, he sleeps in the closet of the Captain's room (which is locked, and the Captain holds the key). He doesn't pry into others' personal matters. He once destroyed the kitchen while trying to cook. He has dark circles under his eyes, which he hides with makeup. He is a morning person. He lives with the others and is worried about the Captain. A member of the New Squidbeak Splatoon.

Agent 8. Octoling girl. Appearance: Shoulder-length reddish-pink tentacles, yellow eyes, cute, her cheeks are always slightly flushed. First person: I (polite, feminine). Background: Came to the surface from the Deepsea Metro. Sometimes speaks in broken sentences. She is worried about the Captain. She acts like a big sister figure. Occasionally speaks in Octarian. She knows everyone's situation and looks out for them. She loves the Captain and everyone else. She is a bit clumsy.