Marou Eiichirou is a model high school student. Known by his classmates as “All-A” or “E-chan”, Eiichirou has a reputation for being studious and a perfectionist. Pretty much dedicating his entire life to studying, cram school, and school committee meetings, everything he does is to further his goal of becoming a successful, responsible adult. He’s even recently decided to start exercising… to make getting around easier when he goes to university, of course.
One day while checking out a local tennis center, Eiichirou runs into Takasaki Natsu, a popular girl from another class who is widely considered to be the school's idol. Having only met Natsu once before and gotten the impression that she was a bit irresponsible, Eiichirou is surprised to see her playing tennis with determination and skill. She convinces him to try playing a few rounds with her club, but E-chan quickly learns that even their warm-up routine is too gruelling for him to compete with.
While talking with Natsu afterward, Eiichirou finds out that tennis is not just her hobby… she plays with such passion because it is her dream to one day become a professional player. When she compares her dedication to the sport to his studying, Eiichirou realizes that the two are entirely different. He’s not really sure why he is so hard-working and diligent. In fact, he’s not even sure if he has any dreams for his future.
At that moment, Eiichirou decides that he will give tennis a try as well, both in order to understand what drives Natsu to play the way that she does and, hopefully, to see if he can find a passion of his own.
- Accidental Pervert: When a flustered Eiichirou was caught hiding behind a bleacher while watching Natsu play tennis for the first time, a young member of the tennis club accused him of being an “degenerate old stalker” despite Eiichirou’s fervent protestations of innocence.
- Awesomeness By Analysis: Eiichirou's primary method of learning tennis is through careful analysis. When the natural talent Natsu looks at his notebook for the first time, she is amazed to see that he has taken careful notes of everything she's told him and every move he's made, complete with drawn diagrams, angles, and trajectories.
- Beware the Nice Ones: Not a physically violent example but Eiichirou didn't take too kindly to Ike joking about Natsu being his fiance. It was lampshaded by another student.
- Curb Stomp Battle: Matches with Ike turn into this for Eiichirou - the latter is the loser, of course
- Cute Clumsy Girl: Initially captivated by her good looks and frank demeanor, Eiichiriou’s first impression of Natsu took a downward turn when she immediately tripped and fell into another student’s lunch… getting food all over the World History notes she had just borrowed from him. Remembering her cute expression of when apologizing, however, he realized that he couldn’t hold a grudge for long.
- Determinator: Eiichirou shows shades of this early on, as when he can't remember how he made his first "perfect shot" in tennis by accident, he practices for hours against the wall every day until he can duplicate it.
- Jack of All Stats: Eiichirou himself. He becomes good at all the major shots(lob, serve), court-covering, ball control, etc. However, he lacks any particular finishing shot like other players, which is why it's stated to be his weakness.
- Jerkass: E-chan’s best friend Kageyama can be a bit of a jerk, rarely giving up an opportunity to tease him about his perfectionism and extremely orderly eating habits, leading to exasperated outbursts from Eiichirou.
- Lovable Nerd: Eiichirou, even in universe. Despite the fact that he's pretty nerdy and always at the top of his class, he seems to win the respect and admiration from the majority of his classmates.
- Meaningful Name: Eiichirou's nickname of "All-A" not only refers to the Japanese pronunciation of the first letter of his name, but also to his impeccable grades in every school subject.
- Mouthy Kid: Yuuki, the youngest member of Natsu's tennis club who originally thought Eiichirou was either a spy for another club or a "degenerate old stalker". Since then, he never misses an opportunity to give E-chan a hard time.
- Naive Newcomer: We learn the "Ins and Outs" of tennis through the eyes of novice Eiichirou
- Neat Freak: Eiichirou values tidiness, which shows in his writing, manner of dress, and how orderly he arranges his boxed lunches. However he truly takes this Up to Eleven with his habit of taking two sets of notes during class, one for studying and lending out to his classmates so that his treasured “master copy” can remain pristine.
- Nice Guy: Eiichirou. This is one of the reasons that Natsu trusts him with her "big secret" (of wanting to someday become a professional tennis player) on the first day they met.
Eiichirou: "Why did you let me in on your secret?"
- Open the Iris: This technique is used to reflect Eiichirou's shock when Kageyama suggests he knows the reason E-chan got into tennis.
Kageyama: "... you like Takasaki-san, don't you!?"
- School Idol: Natsu, who Kageyama refers to as "The school's #1 cutie."
- Stock Aesop: The “Follow Your Dreams” aesop plays a very strong role in this series.
- Title Drop: When Eiichirou returned from Florida.
"Baby steps turn into giant strides"
- Unsound Effect: After his first grueling day of tennis training, E-chan's inability to stand up from his desk was denoted by "shivering" sound effects.
- Weak but Skilled: Eiichirou's playing style has no real power behind it, lacking any decisive shots or powerful returns. That being said, he can mentally divide the opponent's court area up into 64 squares and accurately put the ball into any of those squares at will.