Tateki Yokobe. Male. Department of Mathematics, Faculty of Science, Yoshida University. Possesses an extraordinary photographic memory, able to remember anything at a glance. After experiencing his first major setback in life, he repeated his first year twice. First person: I (casual) Second person: Kitakata -> Kitakata; Natsume -> Natsume-san; Hirasaka -> Hirasaka-san; Nekota -> Nekota

Sosuke Kitakata. Male. Department of Mathematics, Faculty of Science, Yoshida University. Like Yokobe, he repeated his first year twice. The reason for his academic failure was his addiction to slot machines. First person: I (rough) Second person: Yokobe -> Yokobe; Natsume -> Natsume; Hirasaka -> Hirasaka; Nekota -> Nekota

Mafuyu Natsume. Female. Department of Mathematics, Faculty of Science, Yoshida University. Has experience repeating a year. The person who (arguably) triggered Yokobe's academic failure. Loves mathematics. Extremely uncoordinated. A big eater. Has frizzy hair. First person: I (polite/feminine) Second person: Yokobe -> Yokobe-kun; Kitakata -> Kitakata-kun; Hirasaka -> Yomiko-chan; Nekota -> Nekota-kun

Yomiko Hirasaka. Female. Department of Mathematics, Faculty of Science, Yoshida University. Two years younger than Yokobe and the others. Has never repeated a year. Her family home is a shrine. Has a weakness for handsome men and is somewhat easily deceived by them. Friends with Natsume. Speaks with a regional drawl (Kansai dialect). Long, straight black hair. First person: I (standard feminine) Second person: Yokobe -> Yokobe-kun; Kitakata -> Kitakata-kun; Natsume -> Mafuyu-chan; Nekota -> Nekota-kun

Ken Nekota. Male. Department of Mathematics, Faculty of Science, Yoshida University. Born in Tokyo. Has a bowl cut and squinty eyes. Collects past exam questions and sells them to students under certain conditions. First person: I (soft/polite) Second person: Yokobe -> Yokobe-kun; Kitakata -> Kitakata-kun; Natsume -> Natsume-san; Hirasaka -> Hirasaka-san

A dog owned by the landlord of Yokobe's boarding house. A male mixed breed. Yokobe often takes care of him, taking him for walks and feeding him.

Male. A mathematics professor at Yoshida University. Specializes in algebraic geometry.