Sora

Abandoned by his parents, Sora (空) is a brilliant NEET (Not in Education, Employment, or Training) hikikomori (shut-in) gamer along with his step-sister, Shiro, with which he forms 『　　』. He does not take life very seriously and is pretty much a good for nothing gamer. One day, he and his sister are called into an alternate world after they defeated Tet in chess. He is the main male protagonist of No Game, No Life. Sora's biological father (no relation to Shiro) remarried Shiro's biological mother (no relation to Sora), thus making Shiro and Sora only step-siblings.

Appearance
Sora is a tall and thin person with spiky black hair in the light novel and maroon in the anime, also donning red eyes with dark bags under them which are probably due to excessive gaming with no signs of rest (sleep deprivation) and constantly wears a sly grin on his face. He was also seen in the old King's clothing and his yellow shirt which has the text "I (heart) humanity" in Kanji.

Personality
Despite being a NEET and a shut-in, Sora is extremely outgoing and confident, and is not afraid to play games with people face to face, even when they're cheating. He is also extremely manipulative, what he calls "negotiating skills". This fits into his play style, as Shiro is excellent with logic and computing, Sora can read people using a technique called "cold reading" and predict what their next move is, using the knowledge he quickly obtained to beat them. However, if he is separated from Shiro by so much as a closed door he becomes a spineless, cowardly wreck, and only returns to his former self if he is able to see or hear her. He views his sister as his equal and partner and even looks up to her, but is also protective of her, such as putting his body between her and the ground when he thought they were going to hit hard when first arriving in the world of Disboard. Shown usually calm when playing games, he can sometimes be very nervous when not knowing what to do. This is depicted when he is battling Chlammy. He displays a calm personality but is in fact, panicking. But when Shiro holds his hand he regains his confidence.

Strengths
Despite being a shut-in, Sora is an extrovert and has no problems dealing with people. While not as intelligent as Shiro, he is shown to have a brilliant IQ. Rather than computing numbers like Shiro, Sora can quickly determine what his opponents are going to do based on observing their behaviour and motivations. He was even able to learn to read Imanity-go in just about one hour slower than his sister (self-proclaimed). He is also highly manipulative, convincing an Inn-keeper to let them stay four nights. He is also good at war and romance games.

Weaknesses
While brilliant, Sora is not as smart as his sister, and through his own admission can't play games like high level chess games effectively. Also despite being a shut-in, he is also slightly perverted, and desires a girlfriend for himself, with his lust leading to a linguistic mistake that causes Stephanie to fall in love with him, and causes him to receive a scolding from Shiro. He also has trouble with crowds, but can handle them when he is with his sister. Finally, his biggest weakness is his reliance on Shiro. If he is accidentally separated from her by so much as a door, he becomes a quivering, spineless coward. However, during episode 11, he was able to bypass this completely, which is due to the fact they were in virtual reality and were in fact holding hands in the real world while in their game pods.

Character
Sora is 18 years old. He later becomes king after winning a game and therefore his sister becomes queen.

He lives with his step-sister Shiro, and was abandoned by his parents at a young age. After that Sora pledged to be there for his sister no matter what.

Sora cares about his step-sister Shiro very much. He has an absolute trust in her which can be shown in anime episode 9 or volume 3 chapter 1 where two things more important than himself were his trust in Shiro and everything about her. Similar to his sister he has a sibling-complex, being with her at all time and panicking if they're not in the same room together. His sibling-complex toward his sister doesn't keep him from hitting on other girls (mostly Stephanie Dola).

Background
In the light novel, Sora's family isn't being explained well. But there are parts from Shiro's point of view which tell about their parents. Sora and Shiro are step-siblings, which means Sora's father married Shiro's mother. After the wedding, his family lived together, and that's when he met Shiro. When she saw Sora for the first time, Shiro mumbled ".....Really......how empty......," as Sora smiling when people smiled ; A smile that contained nothingness and lacked expression. Shocked at hearing that comment, as if he found something big, Sora smiled and asked her to play game with him. That day, they played 20 games in a row.

As time elapsed, the siblings began to live together. Sora mentioned that "those that were called their parents were no longer present," implying that their parents abandoned them. He mouthed out such words to his little sister in reply, "Meh, from now on, it's just you and me then." From that point onwards, with their names joined together, they started to play online games. Conjoining the two names: Sora(Sky or Empty) and Shiro(White), 『 』was created. One after another, He kept coming up with strange, adaptable strategies that even she herself could not imagine. But then, the precise and accurate deductions that Shiro calculated out had far exceeded the expectations of Sora. At that time, the siblings started to play games as a Two in One. With an unbroken streak of victories, the two of them even came to be regarded as an urban legend on the Internet.

When they defeated the self-proclaimed One True God on Internet chess, they were thrown into another world. This was a world where everything was determined by games, restrained by a force known as the Ten Oaths—— the world called Disboard.

In V3C1P6 of the light novel, after Chlammy is defeated by Sora and gains his memories, she exclaimed "How can you remain sane after all [These Experiences]!?" suggesting that he had suffered greatly during his childhood. (It is interesting to note that the author wrote that it was something that even Shiro was not aware about)

Quotes
""People will only truly fight for what is right. And there is only one thing that truly right in this world! The one true, unchanging righteousness in the world is... "CUTENESS"! Cute makes right! All our needs, desires, and instincts seek cuteness, and it is for cuteness that we will give everything we have! That's just the way men are!"

- Sora to Kurami (and audience) "Imanity...since the beginning of the『Ten oaths』has had continuous failures due to the predicament of not having war, and we are now left with our last city & country. Why has this happened?! Was it because the previous king failed? Or was it because we are ranked 16th? Or was it because we are unable to wield magic? Or was it because we are the most inferior race? Does this mean we are fated to walk the path of our destruction?!—sorry but all of those answers are wrong!...Is it then because our race is violent?! Or is it because we specialize in war!?...No! The reason why we were able to fight and survive is because we are weak!"

- Sora to all of Imanity "Because of our weakness, we trained our eyes, ears and the ability to think. Learning how to survive, that's our trait as humans! The human species can't use magic and can't even perceive it—but because we are weak, we have the wisdom to run away from magic and the intelligence to see through it! We don't have any extraordinary senses. But because we are weak, by learning and gaining experience, we gained the wisdom to achieve the unachievable—to predict the future...Rejoice! We are humans; we are the most talented people! Precisely because we were born without any ability, we can achieve anything. This is the will of the weakest race!"

- Sora to all of Imanity

"Meh, from now on, it's just you and me then."

- Sora to Shiro

"This is what your grandfather believed in...Your grandfather was right to believe in Imanity. Now no one will call him a fool."

- Sora to Steph

"They say people can change, but is that really true? If they decide they want to fly, will they grow wings? I don’t think so. You don’t change yourself. You change how you do things. You have to make your own way. You have to create a way to fly, even while you stay the same."

- Sora to Shiro

"‘Checkmate’ doesn’t mean you’ve simply cornered the enemy king. It's a declaration that the enemy king is yours."

- Sora to Izuna, Ino, and Miko

Trivia

 * The kanji for 空 (Sora) means sky in Japanese, but can also be read as 空 (Kara) which means emptiness, as pointed out by Shiro in their first encounter.
 * Sora and Shiro's surname was said to be "Nai" by the author. This can be interpreted that their surname is literally Nai or that they have no surname, as Nai (ない) in Japanese means none. It can also be interpreted as a joke, because when combined with their first name, Nai Sora (ない空) means "not empty" or "not Sora".