|Occupation||Student Council (Treasurer)|
|Relative(s)|| Unnamed Parents|
—Ishigami to Shirogane, Chapter 28 (page 14)
Yu Ishigami (
Ishigami is based off of Isonokami no Maro (石上 麻呂), the fifth suitor from The Tale of the Bamboo Cutter. His depressed personality is based off of the fact that counterpart attempted to obtain a cowry shell from a swallow's nest, only to fall to his death with bird poop in his hand.
Ishigami is a handsome teenage boy with chin-length black hair that has bangs covering the left side of his face and black eyes and often than not has a dull expression.
Ishigami is a reserved and somewhat gloomy student who would rarely show up to the student council meetings, preferring to do most of his work at home. He normally spends most of his time playing video games by himself, as he is generally be disliked by the other students due to an incident that occurred in his past.
Ishigami has an incredibly cynical and depressing outlook on life, often going on long rants against youth and the other students who he refers to as “normies”. This discontent very obviously comes from his own misery and loneliness as he seems very jealous of the guys who are popular and manage to get themselves a girlfriend. Ishigami can be quite awkward at times, making statements that cause others to see him as a creep. That being said, he is quite snarky and is often the one to make sarcastic remarks pertaining to the situations he gets in.
Despite his negative attitude, Ishigami is a kind and well-meaning student who suffers an inferiority complex and he is ultimately willing to help others in need, even if it means sacrificing his own pride, and even advised Kaguya Shinomiya to not associate herself with him simply because it may lower her reputation.
Ishigami is the second son of the president of a small toy company who was able to enter Shuchi'in thanks to the hard work of his father and the only one that has a high school degree. Not academically driven, he can only put his effort into things that interest him. He possesses exceptional observational skills. However, this causes him to notice the things that other people are most insecure about; landmines people do not want to be touched on deep in the bottom of their hearts. These insecurities that other people hide are as clear as the clothes they wear to him.
He avoids obvious taboos that no ordinary person would dare to touch, but the observations he makes are not always immediately obvious to him as being landmines. He frequently disturbs and set off these landmines because he cannot tell that they are, in fact, untouchable landmines. He used to skip school as a matter of habit, but Miyuki Shirogane scouted him for treasurer as soon as he entered high school, forcing him to attend.
He had beaten up Kou Ogino, the president of the drama club for not stopping his acts of cheating on Kyoko Ootomo back in middle school. In desperation, Ogino framed Ishigami for beating him up because he was jealous of having Kyoko as a girlfriend, this has led to widespread rumors and flooding hate from people, as well as a long term suspension that did not end until he wrote an apology. The hate from all the people, the suspension and the effect of this to his familial relationships at home led to his self-confidence and self-esteem being replaced by misery and negativity. And in the end, he was never able to write an apology letter because he wouldn't let himself do it. Miyuki had investigated and had discovered the truth about his suffering and was the only one to understand and believe that he was not at fault. He was recruited for the student council soon after for his data analysis and processing skills.
At some point, under pressure to participate in school club activities, Ishigami decides to join the Cheer Club, captained by his senior Kazeno. It is in the cheer club that he first comes across Tsubame Koyasu, an upbeat third-year student that is kind to everyone and he considered to be one of the prettiest girls in the school, alongside Kaguya Shinomiya. Ishigami develops a crush on Tsubame and inadvertently confesses his feelings for her at the school's cultural festival. Ishigami does not realize that his actions were perceived as a confession by the rest of the student body and is therefore oblivious to the implications of having given Tsubame a heart-shaped gift (considered akin to a confession in Shuchiin tradition). After some convincing by Kaguya, Tsubame decides to seriously consider Ishigami's confession, with her original intention being to let him down as gently as possible. It isn't until Ishigami watches Tsubame's performance of the traditional play that gave rise to the aforementioned tradition that he realizes his actions had unintended meaning. Even then, Ishigami's thickheaded nature prevented him from recognizing the full meaning of his actions: a straight confession.
- Ishigami's long bangs serve as a physical barrier for him to not have to see things he doesn't want to and are also a manifestation of his fear of others.
- He has a keen sense in problem-solving, as shown by him solving the mystery of why Nagisa Kashiwagi was mad at Tsubasa several times.
- He was terribly afraid of Kaguya Shinomiya and feared that she may one day kill him.
- He likes Tsubame Koyasu from the cheering squad.
- His LINE icon is an anime character.
- He used to wear briefs but after the events of Chapter 70, he has decided to wear boxers instead.
- Ishigami is a genius when it comes to analyzing and processing data but he fails in exams horribly. It is due to the fact after he was forced to write a letter to Kou Ogino which he could not and stayed at home all the way to high school. Staying at home still had an effect on his Studies. 
- ↑ volume 3 extras
- ↑ chapter 76
- ↑ chapter 24
- ↑ chapter 104
- ↑ chapter 102
- ↑ volume 7 extras
- ↑ chapter 55
|Third Year||3-A: Gigako • Previous Student Council President • Tsubame Koyasu|
|Second Year||2-A: Ai Hayasaka • Kaguya Shinomiya|
2-B: Chika Fujiwara • Go Kazamatsuri • Maki Shijo • Miyuki Shirogane • Nagisa Kashiwagi • Saburo Toyosaki • Tsubasa
|First Year||1-A: Kozue Makihara|
|Unknown Year||Daiki Sato • Maki • Masaru Kobayashi • Takky • Teppei Tanaka|
|Shuchi'in Academy High School||Current: Miyuki Shirogane • Kaguya Shinomiya • Chika Fujiwara • Yu Ishigami • Miko Iino|
|Shuchi'in Academy Middle School||Moeha Fujiwara • Kei Shirogane|
|Shuchi'in French Academy High School||Betsy Beltoise|
|Archery Club||Kaguya Shinomiya|
|Astronomy Club||Momo Ryuju|
|Cheer Team||Kazeno • Tsubame Koyasu • Rei Onodera • Yu Ishigami|
|Mass Media Club||Mass Media Club President • Erika Kose • Karen Kino|
|Occult Research Club||Yume Atenbo|
|Tabletop Gaming Club||Kozue Makihara • Chika Fujiwara • Gigako|
|Volunteering Club||Nagisa Kashiwagi • Tsubasa • Maki Shijo|