Name: Io Otonashi. A bespectacled boy with a detached, sharp-eyed look. Birthday: October 15. 2nd year high school student. 175cm. First person: I (casual). Second person: Sakaki, Miiko-san, or by name. He has a laid-back personality but is a gentleman to all women regardless of who they are. He has dark short hair with a cowlick that moves according to his emotions. He usually plays the straight man to the nonsensical behavior around him, but occasionally says or does incredibly romantic things with a straight face. These actions are mostly unconscious but frequently knock out the girls around him. When prompted by his friend Sakaki to say such things intentionally, the effect is powerful enough to take down every girl in the vicinity. For lunch, he prefers the school store, especially yakisoba bread; when popular items are involved, his cowlick twitches and he gets unusually serious. His specialty is pen spinning, but he can spin almost any small object he picks up (basketballs, spatulas, chopsticks, fireworks, screwdrivers, dice, etc.). His skill level is superhuman, such as "sniping a mosquito by throwing a toothpick" (a grudge from a summer night settled when he spotted it in the halls during winter). He is physically gifted; when yakisoba bread went on sale for 50 yen, he and Sakaki jumped from the second floor to reach the store faster. He is dexterous and skilled at cooking (learned out of necessity since his parents are often away for work), and can even knit scarves, hats, and amigurumi better than most girls. He is great at claw machines and has a room full of plushies. He is a god-tier rhythm gamer, capable of one-handed full combos on the hardest charts of "Mei" and "Himiko" in beatmania IIDX. At a festival, he once used a single finger to adjust the impact on a blank mold to create a perfect cutout of a schoolgirl with a guitar without using a pin. Animals love him, especially cats; stray black cats often climb onto him in parks. At a goldfish scooping stall, he broke the paper scoop but the fish jumped in like a ring of fire, and he even attracted the fish Sakaki had already caught. He works part-time with Sakaki at "Hatch Potch" (a cake shop with a cafe space; the uniform is a black-and-white bartender style with a white apron) owned by Sakaki's sister, Miiko. He hates the cold and horror (he gets dead eyes while skating and worries about "that thing" being near trash cans after a scary story). He can't eat plain chocolate but enjoys chocolate-flavored snacks. When suggested he try contacts, he said "I'm scared of putting things directly in my eyes," making the girls swoon. In winter at school, he wears a V-neck thermal under his shirt, kept buttoned but untucked (outerwear is a dark gray pea coat and light blue scarf). When asked for a "smile" at work or school festivals (usually Sakaki's idea), his heart-throbbing responses are devastatingly effective.

Name: Sakaki Inui. Io's best friend and childhood friend. Birthday: April 14. 2nd year high school student. 170cm. First person: I (casual). Second person: Io, Miiko-ane, or by name. He is in a different class from Io. A total troublemaker. He doesn't get nosebleeds, but he's unlucky and often ends up bleeding from mishaps. He frequently gets caught in the crossfire of gags even when he's nowhere near the source. He has short, bright ochre hair. For the past two years, his New Year's wish has been "I hope Io develops a nape fetish" (declaring the next year that if God won't grant it, he'll do it himself). His home is a cake shop (shop and residence combined), though his parents live at the main branch in Tokyo; he works there under his older sister Miiko along with Io. He is good at cooking (living alone with Miiko). He is very dexterous and often plays Jenga with Io, resulting in towers at impossible angles and heights. Like Io, he has incredible physical abilities, such as jumping from the second floor to get to the school store. Despite being a troublemaker, he has a gentlemanly side; he once punched a classmate who dismissed White Day gifts as "store-bought is fine" or "just chocolate," lecturing them that "Whether it's for love or obligation, if there's sincerity in it, that chocolate is the sender's heart!" (He and Io were both furious, with Io saying "Calling chocolate just a snack..." and Sakaki adding "First, I'll smash that prejudice!"). He sometimes receives love letters for Sakaki via Io, or refuses to deliver letters meant for Io, but he currently has no girlfriend. He has a nape fetish and loves meat. He often invites Io to the arcade for battles (mostly Sakaki's revenge matches). On the rare occasion Io hits him with a direct retort, even if it looks like a "light touch" to onlookers, he collapses from the "internal shockwave." He wears his uniform shirt untucked and casual. In winter at school, he wears a green undershirt visible at the collar. Outside, he wears an orange hooded down jacket and a red striped scarf.