Taichi Yaegashi

is a member of the Student Cultural Society and the series' main male protagonist. He attends the same homeroom as Iori and Inaba and is a pro-wrestling fanatic. In class, he is a fairly quiet character, always calm and inconspicuous.

Personality
Taichi is generally depicted as a selfless and considerate individual. He will usually go to great lengths trying to help others even if it comes at his own expense or has no direct benefit to him. This trait has earned him the title, "Selfless Freak" by Inaba. He is a fan of pro-wrestling, and has a lot of respect for pro-wrestling jobbers.

Taichi has also proven to be a very patient man; rarely ever getting worked up and always trying to understand the viewpoints of others rather than starting an argument. Of course, he is certainly not above throwing in a few smart one-liners, but tries his best not to antagonize people. Taichi is also very honest and is hardworking. He usually studies for classes and studies more than the other StuCS members. He never copied homework unlike other students in his grade since he figured out that it defeated the purpose of homewrok and is not a good habit. Taichi has also been shown to be a doting older brother to his sister, Rina, and, to his frustration, he is often accused of being a siscon/lolicon.

In Yume Random, Taichi wishes to "save the world" in the future which is why he chooses to take science courses. His "saving the world" means that he will try to solve problems like energy crisis, malnutrition, and environmental changes.

In Asu Random, Taichi is shown to be afraid of losing his memories of the StuCS and the phenomenons. He constantly writes in a notebook the names of his fellow club members and looks at photos from past events. His habit is so serious that even his sister and mother begin to notice something's wrong.

Key Problem
Unable to bear the pain of watching someone else suffer, Taichi has stated he would rather endure the suffering of others in their place if he could. He is obsessed with helping those in need, even if it comes at the cost of himself. Inaba has likened the severity of this trait to that of mental insanity.

In Yume Random, Taichi's selfless obsession resurfaces when he chooses to use the power Heartseed gave him to try to save as many people as he can. When Inaba asks him who he is living for, Taichi states he's living for everyone else, disturbing her.

Appearance
Taichi is a young man of average height, though noticeably shorter than Aoki. He has short brown hair and eyes, and normally displays a calm face. Aoki suggests that Taichi is quite handsome and he'd be popular if he was more cheerful. Taichi is usually seen in his school uniform.

Background History
Taichi originally wanted to join a "Professional Wrestling Research club"; however it did not have enough members interested in it. As a result, the school placed him in the Student Cultural Society club.

Taichi was a part of his middle school's Baseball Club, and as a result, was quite athletically fit, though according to Yui, by Hito Random, he has stopped practicing.

Family

 * Yaegashi Rina: Taichi’s younger sister. The two are shown to be quite close and Rina often pesters Taichi about his love life. Ironically, Rina is usually the one to give relationship advice to Taichi rather than the other way around. Taichi has also proven to be rather protective of his sister.
 * Mother: Taichi's mother takes care of him and Rina alone due to his father working away from home. Taichi's mother herself is away during most of the day due to work and relegates most responsibilities, including the caretaking of Rina, to Taichi. Inaba suggests that Taichi's mother is neglectful of her family, but Taichi denies such an accusation.

Friends

 * Nagase Iori: A female classmate of Taichi's and the President of the StuCS club. Admiring her expressiveness, Taichi harbors romantic feelings for Iori and confessed his love to her. Believing that Iori was going to die, they kiss while she was borrowing Inaba’s body. Their relationship never fully develops due to the constant complications brought on by each phenomenon and Iori ultimately rejects his confession after realizing their love was too premature. The two remain close friends and Iori constantly teases Taichi about his awkwardness with romance.
 * Inaba Himeko: A female classmate and the Vice President of the StuCS club. Taichi helps Inaba overcome her insecurities by revealing one of his deepest secrets to her. Over the course of the series, Taichi and Inaba develop a strong bond of trust and need for one another: Taichi helping Inaba with her self-esteem and Inaba helping keep Taichi's "Selfless Freak" tendencies in check. After the class trip, Inaba confesses her feelings to Taichi but he turns her down as he's in love with Iori at the time. Despite the rejection, Inaba refuses to give up on him. At the end of the Michi Random arc, Taichi and Inaba begin dating. After Yume Random, Nagase describes the couple to be too comfortable with each other and they are more like a married coupled than dating high schoolers. Taichi finally called Inaba by her first name "Himeko" when they met at the opening ceremony for their first day of class for first year.
 * Aoki Yoshifumi: A fellow StuCS club member and Taichi’s best friend. The two often share adult videos with one another and Taichi is the only club member who abstains from teasing Aoki. Though they act as emotional supports for each other, Aoki admits to being jealous of how Taichi is better than him at helping other people, particularly Yui.
 * Kiriyama Yui: A female member of the StuCS club. Taichi helps Yui get on the path towards curing her fear of men and the two develop a strong friendship. Yui considers Taichi her most trusted male friend.
 * Fujishima Maiko: Taichi’s class representative. Due to Inaba's intervention, Fujishima considers Taichi a bitter rival in her fight for Iori's affections. Despite their supposed rivalry, Fujishima still cares enough for Taichi to offer friendly advice from time to time.
 * Gotou Ryuuzen: Taichi's homeroom teacher and club advisor for the StuCS. The two are shown to be good friends as Gotou is rather lazy and Taichi is always willing to help others. Gotou will occasionally share words of wisdom with Taichi that even surprises himself.
 * Watase Shingo: A male classmate and friend of Taichi. Taichi learns that Watase has a crush on Fujishima.
 * Enjouji Shino: Shino has a fetish for Taichi's voice and goes crazy when he says certain phrases. eg. "Do your best" in Nise Random.
 * Uwa Chihiro: Taichi's underclassmen who he gives advice to sometimes. Taichi was mad at him for a bit after hearing what he did to Inaba during Nise Random but in the end forgave him. Chihiro thinks that Taichi is the most reliable person he knows and asks him for help in Yume Random to resolve a dispute between the Tennis Club and the teacher in charge. Chihiro continues to feel guilty for causing Taichi to lose his memories during Nise Random, but Taichi continues to tell him that it wasn't his fault.

Others

 * Heartseed: Of all the StuCS members, Heartseed seems to take particular interest in Taichi. In the Yume Random arc, Heartseed personally tells Taichi that the two of them are similar.

Trivia

 * According to Yui, Taichi is bad at smiling.
 * Taichi is a big fan of pro-wrestling because he sees it as the art of enduring physical pain and has lots of respect for "jobbers": wrestlers who normally throw fights to raise their opponent's popularity . Moreover this reflects his personality, as he'd rather endure pain himself than seeing other people suffer.