List of Kodomo no Jikan characters

; The bespectacled, good-natured homeroom teacher of 4-1 (originally 3-1) at Futatsubashi Elementary School and protagonist of the series. By his own accounts the product of a normal, uneventful childhood, Daisuke Aoki was an above average student and athlete in his youth and served as a substitute for members of the track and field club in university. While there, he fell in love with an unnamed female peer of his, but she married one of her seniors before he got a chance to confess his feelings to her. Aoki never harbored any resentment or negative emotions over this development, however, and was glad that she had found happiness with someone he believed to be a better man than himself.

After landing a position as a mid-trimester replacement for class 3-1 at Futatsubashi Elementary School, the freshly graduated, twenty-three-year-old Aoki quickly found several of the preconceived, idealistic notions he held about being an elementary school instructor put to the test by his first teaching job, literally from day one: his complete lack of previous experience as an educator left him poorly prepared for controlling or maintaining the interest of a classroom filled with unruly, disobedient students, inheriting a legacy of mistrust from the former teacher, Nakamura. Most significantly, he has to deal with the shameless flirtations of an eight-year-old determined to win his affections. His enthusiasm, positive-thinking, hands-on attitude, and emotional attachment to his students have made it difficult for him to maintain professional objectivity on occasion, often resulting in his butting heads with strict fellow teacher, Sae Shirai, whose distant, traditional teaching style is the polar opposite of his own. In his struggle to come to terms with the demands of his job and become a better educator, he has found an ally in his attractive coworker and direct senior, Kyōko Hōin, who has been an endless source of practical advice, teaching suggestions, and moral support.

Daisuke's lack of life experience has been his biggest obstacle as a teacher. While this fact has never discouraged his desire to help his students, it nevertheless complicates his efforts to grasp the hardships faced by some of them. His lack of experience with women has also rendered him far more vulnerable to Rin Kokonoe's sexual innuendo and Kuro's barbed remarks about his virginity than he otherwise might have been. His tendency to overthink and overanalyze things, obliviousness to female romantic interest, and his inability to read a person's mood have not proven beneficial, either, as evidenced by his ongoing attempts to start conversations or engage in discussions with Shirai in spite of her dislike for him.

From the moment they first met, Aoki's relationship with Rin Kokonoe has been a complex one. Though initially troubled by her actions and unrestrained affection for him, his attitude softened after learning that she was an orphan, and he has done his best to understand the reasons behind her unusual and outrageous behavior. Though they had developed a kind of affectionate working relationship — with Rin subtly using her influence over the other students to help him maintain classroom discipline, among other things — in a dramatic confrontation with her towards the end of his first school year, he was forced to acknowledge the existence of a strong attraction to her. While the initially undefinable nature of these feelings troubled him greatly, even after his reunion with Rin several months later, a chance comment by Mimi Usa led him to realize that he had developed a father's love for the girl (although he tends to have doubts whether this is what he really feels about her). This realization has increased his protectiveness of Rin and led him to become increasingly suspicious of the motives of her legal guardian, Reiji Kokonoe. When Rin and Reiji start to fall out, he decides to move in with them to keep them in check. However, he later moves out on the request of Shirai who saw him leave the house one night. In the end, Aoki comes to terms with his feelings and admits to himself that he does indeed have a romantic attraction to Rin. Though he has come to this resolution, he chooses to stick to his principles and decides that it is for the best to not confess to her and is fine with maintaining Rin's happiness until she is able to grow up and follow her own path, though it may lead to her eventually forgetting or moving on from their relationship and finding someone else. However, once Rin turns 16, she reunites with him and they finally start dating. Provided by Wikipedia