The main heroine. A petite girl who is in love with Io Otonashi. A tsundere, or rather, a "tsun-neko" (prickly cat). She has long hair reaching below her waist, tied at the ends. Her trademark is a curled cowlick. However, while her cat ears are out, the cowlick disappears; they never appear at the same time. Birthday: January 11th. She usually appears cool and is surprisingly good at going along with jokes, showing no mercy when calling out Sakaki Inui or Mayoi Katase. She is sweet and somewhat overprotective toward the serious and sensible Hime Haruno, but she can get jealous of Hime for working at the same place as Io (for reasons like "working together on Christmas Eve" or "having eaten Io's crepes"). However, whenever Io is involved, she instantly turns into a girl in love. Every time he is unconsciously kind to her or gets close, she blushes bright red. See also "IoTsumi." When she gets lovey-dovey or angry, she turns into a cat, with cat ears and a tail popping out. Furthermore, when excited, she becomes lisping and even her monologues take on a cat-like tone. It's no longer just cat-like; she becomes a complete cat. Even when silent, she sometimes emits a dark aura to intimidate others, which also occasionally takes a cat shape. This aura (called "Ectoplasm Cat" according to the subtitles of anime episode 12) can slip out when she is in despair or faints, and it's quite versatile, doing things like biting Io or having a nosebleed. Also, she bites anyone and everyone as an expression of anger or to hide her embarrassment. Furthermore, she gets drunk on lightly carbonated drinks, and when that happens, she becomes uncontrollable. Though not as much as Hime, she is the series' second "nosebleed specialist." When Io's natural gigolo remarks aren't directed solely at her, she sprays a nosebleed along with Hime. When alone with him, her lovey-dovey side takes priority over the nosebleed, but if she hits her limit, fresh blood will bloom at the scene.

Io Otonashi A main character of "Place to Place." A high school student. An all-rounder who possesses extremely high physical abilities combined with a lightning-fast intellect. He is childhood friends with the Inui siblings, Miiko and Sakaki. He and Sakaki are close friends who often hang out together, and recently Kyoya Saibara has joined them as well. He works part-time at the cake shop "Hatch Potch" owned by Sakaki's family and is just as skilled at making sweets as Sakaki. Although Tsumiki Miniwa has feelings for him, he is a total blockhead and doesn't notice at all. He is basically a gentleman toward the opposite sex, but because he is so dense, he does it without realizing the effect he has. As a result, Tsumiki and Hime spray nosebleeds every time he says or does something devastatingly charming with a straight face, and Mayoi can't help but writhe in agony. Also, he is easily liked by animals such as cats and birds, and sometimes they are surrounding him before he even knows it. While he seems to have no weaknesses, he is actually bad with the cold and horror themes. He gets dead eyes when skating, and the moment a scary story is about to start in a horror episode, he escapes using instant movement, even saying things like "I feel like *that* thing will be near the trash can after watching." Note that while he appears to be a sensible and model student, his actual actions are far from being a "good boy" and often involve behavior that would be dangerous even for adults (jumping to the ground from the second floor, shooting insects dead with toothpicks, launching bottle rockets by hand, etc.), so please do not imitate him.

Hime Haruno A classmate of Io Otonashi and Tsumiki Miniwa. A total airhead who is constantly clumsy. Her athletic nerves aren't very good (except for skating). Because she is the only sensible person, she often feels out of place among her eccentric friends. She gets a nosebleed every time she sees a scene where Io is doting on Tsumiki. An easygoing, clumsy girl with a natural airheadedness. She invariably gets a nosebleed whenever a rom-com development occurs. As the story progresses, the amount and frequency of the blood increase proportionally. She isn't very athletic (though she is good at skating).

Mayoi Katase A troublemaker who is always seen wearing a lab coat. It's said that if she ever took off her lab coat at school, it would cause an uproar. She has long, straight-cut bangs that hide half her face, and she wears large ball-shaped hair ornaments on both sides of her head. Her usual behavior isn't as feminine as Tsumiki Miniwa or Hime Haruno, but she is enough of a maiden to feel embarrassed when her stomach growls loudly, to get fired up for Valentine's Day, or to roll around in agony at Io Otonashi's embarrassing lines. She is skilled at tinkering with machinery and can handle anything, from the "demon-remodeling" of a broken stove (attempted → fixed normally) to repairing broadcasting equipment, creating portable sensors for kick-the-can, or building an automatic snowball-making bazooka and an automatic snowball replenisher. Physically, she possesses superhuman athletic abilities beyond the level of an ordinary high schooler, though she is slightly inferior to the truly unreasonable people around her like Io and Tsumiki. However, she is bad at cooking. For Valentine's Day, she mixed frog meat into chocolates calling them "Surprise Chocos," and during home economics practice, she couldn't even crack an egg properly, resulting in a rolled omelet that looked like a Giant God Warrior. A science girl with hidden eyes and a lab coat. An eccentric. She repeatedly commits outrageous acts, but she is a calculated offender who does it all because it's funny. She sometimes conspires with Sakaki when plotting mischief. She has long, straight-cut bangs that hide half her face, and she wears large ball-shaped hair ornaments on both sides of her head. She often makes a cat-like mouth and speaks in a "professor" tone, ending sentences with things like "~jayo."

Sakaki Inui Io Otonashi's best friend and childhood friend. The younger brother of Miiko Inui, the owner of the cake shop "Hatch Potch." While not quite the superhuman Io is, he is still an all-rounder at a superhuman level. With his unconventional athletic ability and a somewhat cunning intellect, he displays incredible coordination with Io. He spends his days warmly watching over the frustratingly slow lovey-dovey atmosphere between Io and Tsumiki Miniwa along with Hime Haruno and Mayoi Katase. However, he and Mayoi, who can't resist the urge to tease, usually end up teasing Tsumiki and getting counterattacked. Regarding his female friends, it's "friendship over romance," and for now, there's no sign of development in that direction; like Io, he is also a gentleman. Also, he has incredibly bad luck, getting caught in the crossfire of events at a supernatural level and suffering painful consequences. His bad luck is second only to Kyoya Saibara in the series. He has publicly declared his "love for napes" in the story and seems to want to teach Io about the wonders of a woman's nape.