|“||Eh? There isn't that club? Then can I try to establish it? It needs five people? I can gather them real quick...||”|
Light-hearted and silly by nature, Aoki can always be counted on, even in the most tense situations, to crack a joke and be himself. Despite his goofy personality and shameless pervertedness, Aoki has been noted to be quite perceptive and is, at heart, an honest character who only has the best of intentions. Aoki has also proven to be a very resilient person as he is regularly berated for his antics by his fellow club members, but he never stays down for long.
In Yume Random, Aoki intends to work at an office and have a stable job after graduating, and plans on taking Art courses. To everyone's surprise, during his third year, Aoki decides to attend a university after all and study economics.
Generally speaking, Aoki can be considered the only StuCS member with no serious problem and is capable of thinking rationally even in dire situations. For example, even when his father was fired for being falsely accused of sexual harrassment, Aoki refused to use the power of Dream Perception to clear his name because he knew there would be repercussions if he did so and he would also drag others into the situation. As such, Aoki's greatest struggle is not internal as with his friends, but a matter of what he is capable of doing for others, and in some cases, what he shouldn't do for others.
Aoki is a young man with dark brown eyes. He is the tallest among his friends and his distinctive blond hair is divided down the middle. Aoki is usually seen in his school uniform.
Aoki originally wanted to join a "Players' Club" and despite knowing that Yamaboshi High did not have such a club, he still wrote it down as his first choice. As a result, the school placed him in the Student Cultural Society by default.
When Aoki was in junior high school, his first love was Nishino Nana. However, Nana eventually moved away due to her parents' work. Later during Aoki's second year of junior high, a girl in his class died in a car accident. Realizing how fragile life is, Aoki swore to live life freely so that when he meets his end, it will be without regret.
Aoki lives with his father, mother, and older sister. His father and sister are usually out working during the day. His older sister is very fond of drinking, often coming home drunk from parties and asking Aoki to buy alcohol for her. Aoki feels that he is a burden to his sister and that he is stopping her from finding happiness, though she denies this.
- Yaegashi Taichi: A fellow member of the StuCS club and Aoki's best friend. Aside from sharing adult videos with each other, Taichi will often act as an emotional support for Aoki during stressful times. Despite all this, Aoki expresses slight jealousy towards Taichi, envious of how good his friend is at helping others, especially Yui. He visits Taichi's home often, but his visits become less frequent after the phenomenons begin. Aoki and Taichi's friendship is an enduring one, and, to their frustration, the two have been mistaken for lovers by Nishino Nana and Rina.
- Nagase Iori: The president of the StuCS club. Due to having similar natures, the two are shown to be good friends and often work together to mess with their fellow club members.
- Inaba Himeko: The vice president of the StuCS club. Inaba is often the person to keep Aoki in line when he gets carried away with his antics. Despite all the merciless punishment and insults she gives him, when all is said and done, the two consider each other good friends.
- Kiriyama Yui: A classmate and fellow member of the StuCS club. Aoki has made multiple love confessions to Yui in the past and she has turned him down each time, though she gradually warms up to him. Because of his annoying antics, Aoki often finds himself on the recieving end of abuse from Yui, both physical and verbal. Never wavering, Aoki swears to make Yui happy, and it is through his efforts that Yui eventually manages to overcome her androphobia. During the Michi Random arc, Aoki declares that, despite feeling useless in the midst of the many phenomenons, as long Yui cares about him, he will never give up. In Yume Random, Aoki's relationship with Yui becomes strained due their conflicting morals on how to respond to the phenomenon. The two later make amends and, after a confession from Yui, they begin dating. Kiriyama teams up with Aoki for the Couples Battle Royale in Precious Times. One of the competitions in the Battle Royale was a competition to find out who can say the most embarassing thing about their partner they were dating. When it is Aoki's turn, he begins explaining that everytime he and Yui kiss, she does something. However, before he can finish, he is knocked out by a kick from Yui to his "most important part."
- Nishino Nana: Aoki's first love. They dated during their first year of junior high, but had to break up when she moved away at the end of that year due to her parents' jobs. Aoki claims she looks similar to Yui.
- Heartseed considers Aoki the most boring and ineffective of the group.
- Strangely, Aoki's friends never use his given name when referring to him. He originally wanted the other members to call him by his first name but everyone decided "Aoki" simply fits him better and calling him "Yoshifumi" did not feel normal.
- He is often called Ahoki (アホ木), which is a contraction of "stupid Aoki" whenever he says something obvious or doesn't make any sense.
- Aoki is shown to be self-conscious about his manhood.
- Aoki has proven to be a terrible Othello player and most people win against him easily.