Shinichirō Isumi (伊角慎一郎, Isumi Shin'ichirō) is one of the oldest Insei in the series.
Often considered too sweet with no back bone, Isumi is generally nice and treats everyone with formal behavior. There was only one instance where he talked back to someone, Ochi, who had berated him for weeks and lost three game straight.
Isumi have shown emotional problem being affect by word or pressure which was one of the reason why he wasn't able to past the Pro exam after taking so many and despite the fact that he was the number one Insei however he was able to matation calm and control at certain time and eventually learn how to control during his time training in Beijing
Little is known of Isumi's history, other than he liked to play go at an early age, a common trait to most Go players.
Isumi makes his first appearance when Hikaru joins the Insei class. Although close at first, Isumi didn't look down on Hikaru.
Once Waya took a liking to Shindou and started bring him along with training, the three boys gained a friendship between each other.
Pro Exam Arc
This proved to be the start of Isumi's downfall as when he and Waya brought Hikaru to a Go Salon, it was shown just how much potential he had, scaring everyone at Pro Exam.
Throughout the exam, Isumi was one of two players with a winning streak until he played Hikaru. Being nervous of Hikaru's strength, Isumi used nearly half the allowed time during the first half of the game, something that was not usual for Isumi. During the game, Isumi's mind was so cluttered that he placed a stone on the wrong side of atair (a move where in one stone, the opponent who lose a piece). After already taking his fingers off, he grabbed the stone again and put it where he actually wanted. This was against the rules that under normal circumstances would make the player to lose the match.
Under great pressure, Isumi resigned, both boys being effected negatively by the outcome. Not being able to regain his normal game again,and suffer two more lost later Isumi play against Ochi when Ochi berated him Isumi angerly tell him Shut up and soon Isumi regain his normal game and beat Ochi as the pro exam contiune Isumi soon play against Honda when Honda make a comeback move unable to turn the tide Isumi resign and suffer another lost at the end of the Pro Exan Isumi hope that he get a chance to for a play off if Hikaru or Waya lost their game but did not as both Waya and Hikaru won and both of them past the pro exam Isumi didn't make it to becoming pro for a third time and started to ask whether if he was able to succeeded.
Chinese Go Association Arc
After dealing with that, it was heard that Isumi stopped playing Go because he was too old to be an Insei, though there was a time before he was brought up again.Some time later Isumi agreed to go to a good will tournament in China, Beijing, along with a few of his older friends who were already pros, where he played a young player by the name of Zhao Shi. Isuimi unfortunately lost again but instead of losing hope, he decided to stay one more day to play Zhao again to prove to himself that he isn't lost.
One of the head teachers at school that the matches where held told Isumi that Zhao had left already for another event for three days. This didn't stop Isumi and choose to stay until Zhao had returned.
After hearing so, the instructor invited Isumi to study at the school until then, saying that he could stay at a nearby hotel. Even with the language barrier with most of the people, Isumi think this is good for him. The teacher showed Isumi around the school until Isumi met a young pro, Le Ping, who at first Isumi mistakes for a small clone of Waya.
The teacher asked Le Ping to play Isumi as a friendly gesture. The game goes horribly for Isumi as he underestimated Le Pings strength and looses yet another game.
He then meets Yang Hai who is one of the only players in the school who can speak Japanese and offers to let Isumi to stay in his dorm room for the dew days though Isumi respectively declines due to wanting to be alone.
After stopping for a break and looses another game, Isumi is called by his father who asks what is going on. That is when Isumi decides that he will be staying in China for two months to train for the next Pro Exams.
Once leaving for the day to find a Hotel, Isumi goes back to Yang Hai in dorm 303, hoping the offer still stands. Yang hosts Isumi but once finding out that Isumi lost to Le Ping, he says that if Isumi is weaker than a child, he can't stay. Yang then tests Isumi with a game of Go where it is then known just how strong Yang is. Though not being clear, Isumi assumes that Yang thinks Isumi is worthy of staying and beings to mentor Isumi for the duration of the two months.
In the next two days Isumi plays and loses all his matches and when finally his original opponent, Zhao Shi, returns, he tries to challenge him to another game, but Le Ping interrupts and asks to go bowling. When Zhao asks what is going on, Le Ping explains that Isumi is a weak player who is trying to train. Yang Hai overhears this mocking and begins a bet with Le Ping, saying that in one week Isumi will be stronger than Le Ping. Le only agrees if Isumi loses, Yang has to stop bugging him to study.
Later than night Yang begins to teach Isumi how to control ones emotion when playing Go. Not even considering the possibility of mastering self control, Isumi was in awe by this revelation.
During that week of training, Isumi played well, gaining compliments from the students who lived there. He even won a against one of the pros by the name of Chen Yi in a league game.
On the day that was scheduled to be the game between Le Ping and Isumi, Yang purposfully waited to get Le Ping frustrated, even strategically whispering in Isumi's ear, making Le Ping think that Yang was giving some tactic.Once figuring out the near cheating ploy, Isumi rushed to Le Ping, apologizing for the wait, and then took off 20 minutes of his game clock. Isumi then won the game by 2 1/2 points.
After the loss, Le Ping become more willing to play just to try to beat Isumi. This was actually a good thing for both players because Le Ping was theatened to be sent home because of his lack of studying.
When the two months in China was over, Isumi came back to Japan for the Exam, though wanted to Hikaru one time before hand, to prove that he has gotten stronger. Little did he know that Hikaru had, at the time, given up in playing.
Thankfully for both Hikaru and Isumi, after pleding, Hikaru agreed to one match. Though it isn't clear who won, it didn't seem to matter because both Hikaru and Isumi gained everything back that they lost; Isumi his confidence, and Hikaru, the chance to play again without hating himself.
Later, Isumi went on to the Pro Exams and had the record for most wins by never losing one game. Eventually after becoming a pro, Isumi climbed up in Go world, even beating Honinbo Kuwabara, one of the best players in Japan, with a handicap.
Isumi is an above average player for his age and has time and time again proved himself to being called that. Isumi has the ability to clam himself when facing a tough move. Although not a prodigy like Akira, or has the unknown potential such as Hikaru, Isumi is part of the wave of 'young and strong' Go players that have been popping up lately.
Initially having trouble controlling his emotions while playing hard matches, after learning for Yang Hai, Isumi greatly increased his skill. From always playing only Insei for years, Isumi skill will grow for now being allowed to go head to head with higher dan professionals.
Best friend and rival. Though being the reason why Isumi lost his chance at becoming a pro, Hikaru was also the reason why Isumi is now stronger than ever.
Best friend and rival. When they met isn't really touched on, it is assumed the became quick friends during the first time they both entered the exam to be pro. Isumi is stronger than Waya, but still considers him as a rival.
Friend. It is not clear is Isumi considers Yang a rival. Yang Hai was one of the few people that was nice to Isumi, which gave them a mutual relationship. Even after a time skip, during the Hokuto Cup Tournament, Isumi and Yang still appear to be close.
Friend. Le Ping considers Isumi his rival. After first mocking Isumi for being weak, then being proven wrong a week later. Le Ping has grown frustrated with Isumi's strength and challenged him over and over to games until he can dominate over Isumi.
Isumi sees Le Ping as a great player, but can't help but kinda feel like an older brother, even taking care of Le Ping when he had a stomach problem. It is not known if Le Ping still tries to beat Isumi even after he left for Japan.
- He apparently likes denim jackets.