Manga: Chapter 107
Daigo Yashiro (社 大吾, Yashiro Daigo) is a man who was travelling around the island with Junichi Mutou. He was originally part of the group that took refuge in the pyramid and was travelling around the island to find the mysteries behind it. However, he later escaped after Takashi Nishikiori took reign over the group.
Daigo's facial features include slanted black eyes and black eyebrows. He has black wavy hair that extends to the bottom of his neck that he combs backwards away from his face, but nevertheless he does have a few strands of hair going down his face. He is seen wearing a black top with a white long tie. On top of that, he wears another black top with grey stripes with it unbuttoned. Similarly, he wears black pants with grey stripes and a white belt. He also wears leather snake printed shoes and is commonly seen with a white cigarette in his mouth.
Daigo and Junichi encounter Akira’s Group, after running away from the Pyramid after Takashi gained the command over their group. They are bound and questioned by Akira's Group about their motivations. At night, he escapes from his bonds using his knife but is recaptured along with Junichi after they inspect The Tower. Daigo snidely avoids his questions, enraging Maya Miyauchi who threatens to beat him to death. Everyone in Akira's Group is annoyed by his uncooperative attitude.
Daigo proposes for the two groups to exchange information, pleased that they know so little. However, after hearing what they have to say about Miina Isurugi he laughs at them for their naivete and suggests that she was lying. When he nears Miina, Maya blocks his way. Kicking up sand to temporarily impair her vision, he slams his knee into her chest, downing her.
He is very pleased and laughs when Junichi, in the midst of the disturbance, has grabbed Miina. He threatens the others not to approach them or attempt to find them as the three of them exit the camp. Daigo takes over withholding Miina once they have left.
Daigo interogates Miina about what she knows and presses his knife into her neck, drawing blood. He is pissed off at her silence. Though annoyed, he stops hurting and questioning her when Junichi attempts to reason with him, reminding him why they escaped from Nishikiori as they both disagreed with his methods. It shows that he isn't as evil as he was depicted earlier.
When Miina Isurugi (Fake) reveals himself after defeating Junichi, he turns his attention to her and leaves Miina calling him another brat. The two fight with him getting several hits in and knocking Miina to the ground. However, when he reveals that he only acted as a decoy, Daigo's eyes widen as Rei Ooguro appears from behind, knocking him out cold with a strike to the back of his head. Rei remarks that he went completely limp at the swing.
For the third time, he is tied up at Akira's camp and more uncooperative and uncompromising. However, Junichi discourages his attitude and introduces them both to the group. He is irritated and warns 'ossan' not to spill everything. In resignation, he begins to tell their story before their arrival to fulfil his part of the deal between the two groups. They are released from their bonds as he tells them about the Pyramid, the 'monstrous' individual ruling over them and well as showing pictures on his solar-powered phone.
When they escaped from the plane, they were a large group of mostly adults and three schoolchildren. They were led by Watanabe, a young man who owned a small company. He was a leader Daigo admired and praised and Ryouichi Suzuki remarks he would have been very impressive if someone like Daigo spoke well of him. Watanabe kept his group on the move to avoid becoming prey for the animals. Some time ago, they found the Pyramid, set up camp and proceeded to excavate the place, Watanabe working alongside the others as they believed inside was an airplane provided them a way out of the island. However, tragedy struck and an illness took hold of everyone, leaving them weak and immobile. Takashi bribed them with a cure under the condition they now worked under him. Soon, everyone had promised him, even Watanabe for the sake of his daughter's life. However, Nishikiori refused his pleadings as he needed to die for him to become the leader. Daigo bitterly remembers Nishikiori laughed as both father and daughter perished.
After losing a rock-scissors-paper game with Junichi, it is decided that he will be the one to guide the exploration group towards the Pyramid. He reassures his companion that he will be fine and will leave after they are within site of the Pyramid. He is wary and reluctant to return anywhere near the Pyramid.
Daigo leads the exploration party towards the Pyramid, estimating that it would take a week but is surprised when it takes only 4-5 days as the women in the group weren't too much of a hindrance. He helps Akira Sengoku decide where to stop for rest and reveals some more information.
There were 3 students in Nishikiori's group and also a teacher. He describes a teacher frequently reading porno and his physical appearance such as side whiskers, glasses, roughly in the 40s and his messy hair who didn't seem to give a damn about the students. He messes up his hair while describing Ugen Kokonoe with a surprising likeness between the two. he then takes out a haircomb and promptly fixes his hair.
On the first night, he smokes and is annoyed at the commotion caused by the others. Darkly, he thinks to himself that they should enjoy what they could presently as, upon arrival at the Pyramid, he thinks they will discover true evil and some will not survive.
When they can see the Pyramid, he tells them that he has fulfilled his promise and will return to their camp at the Tower. Some of them are shocked, under the impression they would be led straight there, but Akira is more understanding, thanking Daigo as Akira recognises this was painful for him due to Daigo's own experiences.
Daigo had grown attached to them to some small degree. Instead of leaving immediately, he reminds them of the danger Nishikiori is and warns them to approach carefully.
He is temporarily absent from the story until Kouichi’s Group had exited the Lighthouse. From the map, Kouichi Yarai heads towards the Tower believing (correctly) that Akira would be there as he needed to find help for Motoko Kurusu. As Kouichi's Group travels through the forest, the girls hear a sound and notice a figure in the greenery who is revealed to be Daigo. Saki Segawa believes he is a Yakuza member due to his looks.
Daigo asks if they are heading to Nishikiori since Motoko is plainly ill and Nishikiori is a doctor. He tells them in little detail that Akira is also there and, once more, leads a group towards the Pyramid who do not recognise the danger Nishikiori poses due to manipulation of his power as a doctor.
When escaping from the Pyramid, Daigo is shocked to find the Akira’s Pyramid Party once more and that they were the cause of the commotion. As Akira enquires why he is there, he messes up his hair and pulls his eyes up to describe the appearance of a tall blonde man who looked 'as strong as an ox!', later brushing it back in place. They all proceed to return together to the Tower, Daigo once again leading the way. Ugen takes his cigarette and knows Daigo swiped his cigarettes when he escaped. Daigo ignites another cigarette and dismissivelty asks if Ugen minds leaving the other students. When Ugen says that he is supportive of student independency, Daigo is amused and says that Ugen is irresponsible. Once they are back at the camp, there is a joyful reunion between the school students. In the background, Daigo reunites with his companion, Junichi, seeming casual while Junichi is happy at his safe return.
Failed Experiment arc
Daigo has a small role in this arc and makes a few appearances.
When Akira’s Group attacked the Chimera to save Miina, his is hiding under cloth as did many others.
Once the Chimera was in the right position, Daigo is seen attacking its underbelly as with most others from Akira’s Group. When it is finally defeated, Daigo gives his knife to Akira so he is able to cut through the Chimera's stomach.
As they are travelling to the Pyramid, Akira asks Junichi about their mission and Junichi advises them to quit while they're ahead because they won't be able to do it. This sparks some anger from the others but Daigo defends him and says he understands Junichi's point of view.
He describes that Nishikiori's control over his slaves is similiar to the Nazi's use of whistle blowing where the people, due to being bullied and punished, grew too afraid to even think of revolting. Daigo doesn't believe the slave will betray Nishikiori due to the strength of his control over them.
Saki remarks that he is well-informed for a Yakuza. Finally sick of being mistaken as a Yakuza all the time, he snaps that he is an adventure novellist, suprising everyone. While no one recognises his name, and he comments his novels aren't targeted at people their age, they are impressed. Expectant of something interesting, they ask Junichi for his profession, which is less interesting as a bonesetter. Momoka Kirino brings up that Junichi had told her before he did judo. Daigo is amused by the interest sparked by this and tells them Junichi would be useless regardless in the upcoming fight. To demonstrate, he pours a red liquid from his flask onto Junichi's hand and reveals it to be animal blood. As Junichi throws up, Daigo explains that he gets sick at the sight of blood.
After Akira and the others have caught Nishikiori when his group was blinded by the Gigaflash DX, Ugen explains the effect of the bomb to the girls. Ugen says that while it won't kill, it will blind people temporarily and proceeds to laugh madly. Watching, Daigo is unnerved he is a teacher since 'he's crazy'. Momoka compliments him for making the others a form of shades that protected them from the glare of the Gigaflash and he tells them he learnt it from Inuits in Alaska who needed it to protect them from the sun's glare reflected in the snow.
Daigo was fighting in the others the first time. However, like the others, he is beaten badly once Nishikiori implements his plan to beat the helpless men under threat of hurting the women so they are unable to react. Afterwards, when Nishikiori's men move to leave him with the others, Nishikiori stops him. He orders them to put both Ugen and Daigo in jail, perceiving them as threats and probably guessing they had the ability to destroy his plans.
Both he and Ugen are released from prison when Sengoku is victorious in his defeat of Nishikiori and releasing the slaves.
As Akira first begins to suspect Junichi as the missing doctor, Daigo laughs, amused, and tells him to stop as Junichi is a 'perfect good-for-nothing', mentioning his weakness to blood.
Once it becomes clear that Junichi is the doctor and is isolated from the others who begin supply-gathering for Motoko's operation, Daigo is pissed off as he approaches him. He is angry at the fact Junichi refuses to assist the others, saying that even though they are just kids, they are desperately trying to save a life. Junichi is hurt and angers when Daigo angrily asks 'Do you have no shame?!'.
Junichi says he can't, He reminisces of a tragic day when he failed to save a boy's life after a traffic accident. Afterwards, he reveals the boy was his son and since, his hands shook in the surgery room and he vomited at the sight of blood. Daigo becomes quiet after this, stunned as the others are.
As the others pass on their hopes for Junichi to operate successfully on their teacher, while Daigo doesn't hold his hand and encourage him, he comes with Akira who does so.
As Junichi has finished operating, Daigo finds him and approaches from behind and apologises for his callousness earlier though Junichi dismisses this and said he should have apologised. If he had been braver earlier, more would have survived. Both become quiet as they reflect.
Daigo comments this event was a reminder to them all. Despite their strength, the others were but schoolchildren and it was up the the adults (Kanako Oomori, Tooru Rinzai, Rei, Seigou Komiyama, Hideo Igarashi, Ugen, Junichi and himself) to support them.
Tower of Death arc
- Daigo appeared on the cover of chapter 131 with cat ears.
- Because of his business suit people think he is with the Yakuza.
- He is one of several characters who smoke.
- He is the Third person to use an electronic Survival Item.
- In chapter 155 he says that before the island he was a writer.
- He's usually in a relaxed position with his hands in his pockets and fights using his legs mostly, like Kouichi.