Senku Ishigami

Senku Ishigami (石神千空 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, 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. Senku is a young male with an average build. His characteristic hair has two bangs going across his eyes and the rest sprays up, like a plant. His hair is a light, dirty blonde with dark green tips. He has red eyes. After his de-petrification, he has two diagonal marks reflected against each other on top of the beginning of his eyebrows. His clothing remains the same. Before the Stone Apocalypse, he wore his school uniform. In the Z=1 Stone World, he switched to wearing animal skin clothing in a rudimentary manner. After Yuzuriha's de-petrification, he gets a clothing redesign. He wears the same animal skin, but this time in a caveman style, patched up in a better manner. Albert Einstein's mass–energy equivalence formula (E=mc²) is printed across the front of his clothes, serving as a "motto". Kohaku states he has the face of a "lady killer" implying he is handsome. Senku has an over-the-top attitude that comes in the form of comedy and leadership. He is confident in himself and has the ability to back it up.

Even so, he never lets his confidence clouds his judgment or belittles those around him. Rather, he serves as a source of encouragement and inspiration to everyone around him. Because of his wits and his caring nature, people tend to gather around him colleagues and supporters alike. Although he has a strong sense of justice, he doesn't let the rules dictate his actions and can be cunning at times to get what he wants. He often acts as if he builds inventions and uses people for his own interests and in the name of science, but beneath his arrogance and manipulative nature lies a genuinely kind heart. He goes against Tsukasa, stating he would use science for the sake of saving the seven billion people petrified. In a flashback, when asked who he would choose between saving himself, his friend or his lover, he answered he would find a way to save everyone. He proves this true when he chooses to "sacrifice" himself to save his friend Yuzuriha from Tsukasa at the cost of revealing to him the ingredients and process for the elixir that would de-petrify the stone statues. similarly, he built an automobile for the express purpose of being able to transport the elderly with limited mobility despite claiming he did it for the sake of faster travel to the enemy headquarters. He even willingly was going to walk into a very obvious trap set by Tsukasa to save Chrome (as Tsukasa knew he would never abandon his friends) though luckily Chrome cleverly managed to escape on his own. On a side note, he seems averse to the idea of romance. He was disturbed when he met Kohaku and she claimed she "fell for him" before clarifying she meant it in a platonic manner and was interested in his actions more than anything. He calls a brain filled with love the most illogical and seems against the idea himself though he is shown supportive of Taiju's and Yuzuriha's relationship along with Chrome's feelings for Ruri. In addition, when he married Ruri, he immediately divorced her rather than take advantage of the situation and seemed disturbed when Nikki claimed to have fallen for him (though she hasn't shown increased romantic interest since). Senku strongly believes in science, believing that there is nothing science cannot solve but that science is a steady pain in the ass long process of understanding the rules behind the phenomenon.

He refuses to lie about anything regarding science, as Tsukasa asked if Senku would promise to quit pursuing science and Tsukasa would not kill him, Senku flat out refused. He will never lie when it comes to the capabilities of science (partially due to his own straightforward personality). Senku is perseverant in his endeavors, having worked solo for six months initially in creating the de-petrification elixir. He also has the habit of saying "ten billion percent chance" as his catchphrase for when he is sure of something. He loves science and particularly loves to create new inventions. He will also use his accomplishments and inventions to win people to his side, such as recreating ramen from scratch to win over some of the villagers to help him in his process to make iron. He tends to be conniving and straight forward in his opinions, which gets on the nerves of some of his friends and makes him a terrible negotiator. Nonetheless, his intelligence, charisma, and compassion for his friends allows him to win many allies and even move some of his enemies, most notably Tsukasa. Senku Ishigami is a genius with a vast amount of scientific knowledge. He is able to invent various kinds of tools and gadgets in a short amount of time with ease. As a child, he designed and built a functioning miniature rocket ship. Senku also possesses an analytical mind, being able to correctly discern the situation he is in. Even in his pre-teens, he was intelligent and sharp-minded enough to create advanced machines. Senku has shown knowledge in chemistry, physics, engineering, geology, biology and mathematics. In addition, he has enough medical expertise to save Gen through blood transfusion, create aspirin and accurately diagnose and cure Ruri of her pneumonia, and cryogenically preserve Tsukasa until they could find a proper cure for his injuries. He has his limits, as he admits he isn't a vehicle architect. He also can't compare to Kaseki in terms of building skills, as Kaseki has far more experience than him.