The main protagonist of the story. He is a seventeen year-old high school student whose relationship experience with girls only includes unrequited love. While he holds hope and curiosity toward love in his heart, it is the appearance of Rin that prompts him to take action. In general, Hiro is optimistic, but due to his lack of experience, he sometimes says and does dubious things. He lives together with his working mother; his father passed on when he was young.
A girl who has been in the same class as Hiro, the protagonist, since her first year of junior high. As such, she has a certain familiarity to him characteristic of an old friend. Full of energy, she regularly participates in track team activities. Her personality prevents her from keeping secrets from others, but her forgetfulness and inability to keep things organized are her faults. She is uninterested in womanly things such as cooking and fashion, but is trying to learn.
Hiro's "sempai" one year above him, she is a good-natured girl, cheerful and openhearted. She pays close attention to her surroundings, and gets along with just about everyone. She is something of a do-gooder, helping out her friends when they are in need. She seldom takes initiative, but always has a firm grasp of the situation and can make level-headed decisions. She can sometimes be worrysome to the point of being naggy. She hates being called "Yamada".
A timid girl, she is often by herself even on campus, giving an impression of constant isolation. She rarely actively converses with others, and never shows anyone her smile. Always in her own world of solitude, she dislikes sharing space with other people. She has trouble depending on others, and tries to solve her problems on her own. Because of this, others view her as being coldhearted.
A girl brimming with curiosity, her principle is to enjoy life. She is free-spirited and does not think too much about anything. She often causes trouble for those around her, and since she hates being bothered, she sometimes outright ignores people. She dislikes roundabout ways of speaking, and even makes requests in a straightforward manner. On the surface, she does not appear to be one to chase the fish that gets away, but there are times when she feels a little lonely. In general, she approaches relationships with others with a positive outlook.
A first-year high school student. She started liking Hiro ever since she was in junior high, and has been secretly pining for him ever since. She yearns to be an adult, and has something of a complex about the way she looks like a little girl. She has a gentle and kind disposition, but can have wild mood swings, and sometimes acts upon wrong assumptions, but overall is a very diligent girl. It is because of this diligence that she is almost never disliked by those around her.
A high school student in the same class as Hiro. He hangs out with Hiro in his free time. He is usually quite hyper, which doesn't always mesh with others around him. He has been in the Kendo club since junior high, and is also a huge anime and video game otaku.
She is a cell phone spirit of sorts, who supports Hiro's love life. Her appearance is that of a little girl, but she is actually her owner's cell phone given form, with all of its original functionality intact. Her mission is to fulfill her owner's love within a set amount of time. She declares to Hiro that if this mission is not completed in time, her very existence (along with Hiro's cell phone) will be destroyed. Along with performing her duties as a cell phone, Rin also encourages Hiro when he is in need, and reports schoolgirl data to him.
