Senku Ishigami

Senku Ishigami ( Ishigami Senkū) is the main protagonist of Dr. Stone, and is friends with Taiju Oki and Yuzuriha Ogawa. He is known for his catchphrases, one of which is "Ten Billion Percent". He was de-petrified half a year before Taiju was, and eventually created the Stone Formula with Taiju's help. In the Stone World, Senku wants to rebuild civilization and establish a Kingdom of Science.

He was the first-prize champion in the Village Games, and currently holds the title of Village chief in Ishigami Village, where he is widely a legend thanks the late Byakuya’s influences through out his founding village’s community.

Senku is the de facto leader of the Kingdom of Science. Later, as a member of the Five Wise Generals, Senku provides the ideas and initative for their large scale plans; he councils with Chrome, Gen, Ukyo, and Ryusuibefore taking action.

Appearance
Senku is a skinny young man with white (light green in the anime,) brush-like hair that spikes up, with two locks of hair that drape over his face, and red eyes. Kohaku admitted that he looks like a "lady killer" to her, implying he is handsome. Luna also expressed an attraction to Senku.

His stone markings are two, symmetrical diagonal lines on top of his inner eyebrows.

Pre-Stone World, he wore a typical school uniform with a lab coat over it. After waking up in the Stone World, he switched to wearing animal skin clothing in a rudimentary manner. After Yuzuriha's de-petrification, he gets these clothes patched up in a better manner. He has Albert Einstein's mass–energy equivalence formula (E = mc2) written in his own blood across the breast of his shirt.

Senku's appearance in the anime

Senku's appearance in the manga

Senku's color scheme in the manga Add a photo to this gallery

Personality
Senku is a straight-forward, confident and highly logical individual who can come off as arrogant. Even so, his borderline-overconfidence does not cloud his judgment, as he is often backed up by his superior and vast knowledge of science. Senku never belittles those who are less knowledgeable than him. Rather, he encourages and inspires everyone around him to do better. Because of his charisma and caring nature, people tend to gather around him, both allies and supporters alike. However, he can act over-the-top at times when he is excited over a creation or at the discovery of something new. Despite his usual appearance brimming with confidence and determination, Senku is not above berating himself, such as when Kohaku noticed the North Star being slightly off its location while he didn't assume so from the amount of time that has passed being petrified.

Senku has a very logical mind, believing that there is nothing science cannot explain, even if it takes a long time for science to properly understand any one thing.

Although he has a strong sense of justice, he often bends the rules, withholds information, and manipulates others to get what he wants, but if only for the better of his allies. He often acts as if he builds inventions and uses people for his own interest (such as glasses, and the automobile), but beneath his arrogance and manipulative nature lies a genuinely selfless and kind heart. This is proven time and time again, particularly when Senku mourns his adoptive father's death. During their decisive battle, Tsukasa notes that despite Senku's apparent cold rationale, his greatest weakness is his inability to abandon his friends, having witnessed his kindness firsthand with Yuzuriha taken hostage.

Unlike Taiju, Senku seems averse to the idea of romance. He seemed disturbed when Kohaku worded her praise for him strangely, claiming she had "fallen for him." In addition, he immediately divorced Ruri, in the few seconds of their marriage. He was also completely unaffected by Amaryllis' attempts to charm him, much to her chagrin. He believes a brain filled with love is most illogical, but he does support his friends, such as Taiju's relationship with Yuzuriha, and Chrome's relationship with Ruri. Despite all this, Gen believes that one day, after all the conflict is over, he may consider the idea of romance.

What Senku lacks in physical ability, he more than makes up for with his determination. He counted the time he was petrified to the last second for nearly 4 millennia, and willingly faced death by Tsukasa's hand because of his refusal to end his science and to protect Yuzuriha without being fazed. Senku also defeats Ibara with his quick thinking and help from Ryusui Nanami. Senku is simply someone who refuses to give up on a task no matter how arduous.

Abilities and Skills
Genius Intelligence: Senku Ishigami is a genius with an encyclopedic knowledge of all things scientific. He is well versed chemistry, physics, engineering, geology, biology and mathematics. Senku is able to easily create various useful tools and gadgets, medicine, and most notably, the de-petrification elixir, despite the limited materials of the Stone World. Tsukasa calls him "the sharpest, most intelligent man in the world". In addition to his scientific knowledge, Senku also possesses great resourcefulness and an analytical mind, seemingly never having a shortage of options at his disposal. For whatever he lacks, he has an ally who can offer their strength. He also possesses great mental fortitude, able to think quickly on his feet and keep his cool in the most dire of situations.


 * Craftsmanship: As a child, he designed and built a functioning miniature rocket ship, alongside many other advanced and experimental machines. However, Senku doesn't compare to a master craftsman like Kaseki, in terms of building skills, as Kaseki has far more experience than him.
 * Tactical intelligence: In addition to his scientific intelligence, he appears to have some skill as a strategist. He managed to coordinate the villagers and even some of Tsukasa's army whom he converts to his side in an effective bloodless war against Tsukasa's Empire of Might. Similarly, he manages to have Kohaku, Ginro, and Amaryllis infiltrate the chief of Treasure Island's harem as spies and manages to communicate with Kohaku and develop a strategy to cleverly gather the scattered petrified pieces of his friends along with the precious stones from the Soyuz chamber.
 * Eidetic memory: Senku remembers every compound and sequence of his inventions. He has never once been wrong in the making of tools for the Kingdom of Science, and has an enormous amount of knowledge in aformentioned science fields.
 * Charisma: Though arrogant and eccentric, Senku seems to have a good understanding of people and how they think. He uses his many creations to charm those who were suspicious of him (like ramen, glasses, and medicine) to slowly warm up to around him. Senku is also a capable leader, who is good with his words, able to motivate and lead the villagers into an effective army against Tsukasa's Empire of Might. He has personally gained the loyalty and respect of his allies (and enemies) through his hard work and determination.


 * Linguistic Proficiency: Senku seems to be fluent in both Japanese and English. He understood Ukyo and Gen's while they were speaking English through the buried phone in order to conceal their conversation from the others present. He was able to speak to understand the discussion between Taiju and Dr. Xeno with no problems.

Weaknesses
Low physical prowess: Senku is below average in terms of physical ability, lacking physical strength. He was unable to hold Homura, a petite woman shorter than 5 feet, after managing to grab hold of her. He also admits that he won't stand a chance against someone as strong as Kohaku in a fight (although it's not really a fair comparison, given how strong she is). In a bonus chapter, Kohaku gives a small description on the physical abilities of the main characters. Senku is at the bottom at around 3 points, Chrome at 5, Ginro at 100, Kinro at 500, and Kohaku herself at 1000. Similarly, Senku has poor stamina, and tends to get physically exhausted rather quickly. He is also very vulnerable to hypothermia, only being able to withstand cold water for a short amount of time.


 * Average craftsmanship: While not bad in terms of craftsmanship, he lacks the natural talent in it. It took him several months to learn how to do pottery, and even then, it could only be considered decent. He has also failed miserably at making glassware, and for more detailed and intricate objects, requires expert craftsmen like Kaseki to make them. He also requires Yuzuriha to piece together the broken stone statues as he lacks her talent and precision.
 * Allergies: Senku is allergic to lacquer. It causes his face and lips to swell up dramatically. 

Lack of cooking skills: While not a weakness per se, he is not an exceptional cook. He is shown to know how to cook, but lacks experience and quality ingredients. While he knows the process of how to make food, most of the time, the more complicated food does not taste good. While he was able to make cotton candy and cola, more complicated foods, such as wine, ramen, and bread prove to be terrible tasting. While in the ramen's case, part of it is due to not having the exact ingredients (he uses foxtail to make flour instead of wheat). When he tries to create bread with all of the proper ingredients on hand for the first time, it comes out so horrible that no modern person is capable of eating it (though the Ishigami Village tribe loves it because they have only ever eaten fish and have never tried bread before).

Bad luck: Throughout the series, despite his high intelligence and ability to overcome obstacles, he tends to run into trouble often due to his horrific luck. Gen, at one point, quips to Senku (while they are trying to make gunpowder to stop Tsukasa's army and fail) that Senku always has crappy luck. In the Petrifaction arc, where he goes to Treasure Island, after all their resources and options have been exhausted as he and the Kingdom of Science are cornered by Ibara, Mozu, and their army, Senku is even forced to use his worst trump card: reviving Hyoga (a rather unpredictable and cruel man willing to manipulate and kill anyone who gets in his way) to have a fighting chance against Ibara and Mozu despite the strong possibility Hyoga will immediately overpower the Kingdom of Science and/or learn of the petrification device afterwards. Later on, Ibara uses the petrifaction device to petrify everyone but himself. When detailing travel by Vikings, a storm hits but they still reach America, due to Chrome. While commencing their exploration of United States, the crew is attacked by alligators as Gen once again makes a remark about how Senku's luck is non-existent and every one of his hypotheses about the worst-case scenario usually turn out to be true.

Trivia

 * Senku's name is composed of "sen" (千 thousand) and "kū" (空 sky)to create Senkū (Thousand Sky), while Ishigami is composed of "ishi" (石 stone) and "kami" (神 god) to create Ishigami (Stone God).
 * Senku shares a motif with Taiju and Yuzuriha in that his name contains "kū" (空 sky) in his name, which correlates to the theme of "land, sea, and sky".
 * Senku has been ranked 1st place in the 1st and 2nd Character Popularity Polls.
 * There have been women who have shown signs of attraction to him. Kohaku claims to have fallen for him when they first meet. Though she clarifies that she means it in a platonic manner, she admits in chapter 22 that he looks like "lady killer" to her. In that same chapter, Ruby states that she is interested in a man who will dote on her and she is so impressed by the ramen that Senku makes that she asks what his type is. He does at one point marry Ruri, but divorces her within five minutes of their marriage. Also in chapter 51, where Senku asks Gen about Homura from Tsukasa's army, Ginro thinks he is stating what his type is while Shovel, Ruby, Garnet, and Sapphire seeming interested in hearing. In Chapter 62, he rebuffs any attempts to take advantage of Homura after catching her. After Senku promises Nikki that he will protect Lillian Weinberg's last recorded song, Nikki also claims she could fall for him, something he casually shrugs off. He was also immune to the charms of Amaryllis, something that took her by surprise because the other males in the group were interested in her. However, due to Senku's focus on rebuilding civilization along with his aversion to romance, he hasn't formed any romantic relationships. In Chapter 107, he is kissed by Kohaku, but shows no reaction. He charms Luna with his kind nature to get information, leaving her interested in him but the others were aware that he was putting up an act.
 * He states Doraemon is what inspired him to become a scientist.
 * He demonstrates a love for video games, making references to Super Mario Bros, Civilization, Dragon Quest, and Monster Hunter (Monster Hunter having a particular shout out in chapter 63).
 * He has three main catchphrases: he claims "10 billion percent" when he is certain of something, "1 mm" when he claims how impossible something is, and "This is Exhilarating ("Get Excited" in the English dub)" when a new development occurs or he manages to further his scientific developments.
 * As the manga tends to be realistic as possible with science, Senku may end up restoring technology to the level of the late 1800s. (Modern conveniences such as indoor plumbing and central heating may be something Senku doesn't know about.)
 * He shares traits with Yoichi Hiruma from Riichiro Inagaki's previous series Eyeshield 21.
 * Grinning when he conducting the best situation to meet his ends.
 * High intelligence, photographic memory, and cunning.
 * Proficient with arithmetic being able to calculate long periods of time down to the last second.