|“||It's time to form Voltron||„|
|~ Shiro's Catchphrase when he asks his team to form Voltron|
Originally an exploration pilot for the Galaxy Garrison, Shiro traveled to Pluto's moon Kerberos with Dr. Samuel Holt and his son, Matt Holt, which at that point in time was the furthest that humans had ever traveled into the universe. While Earth's governments officially reported them missing due to pilot error, the three had in reality been abducted by a passing Galra ship which had been scouting Earth's solar system for signs of Voltron. Dr. Holt was sent to a labor camp, while Shiro and Matt were sent to become fighters in Emperor Zarkon's Gladiatorial Arena.
Shiro's personality is that of a born leader, naturally adept at calmly commanding his team. Although he holds a commanding presence, Shiro is actually quite kind as well as sensitive to the struggles and concerns his fellow Paladins are undergoing or may have. This is highlighted in his patience with Pidge, as he knew that she was Katie Holt due to having worked closely with her missing family members, and sympathized with her loss and understood her grief, frustration, and desire to uncover their fates. Shiro's skills as a leader are further enhanced by the familial bond he forms with all of his teammates. Despite how serious and straightforward Shiro can be, he can also be just as silly and laid back as his friends when he has the chance, such as when his friends were making "laser noises". He initially sided with Keith on knocking it off before engaging in it himself, causing the Red Paladin to appear embarrassed that his leader was acting so ridiculously.
Shiro is a pilot of almost unheard of ability. He is a natural pilot of legendary reputation back on Earth, where his skills made him a hero to many aspiring pilots such as Keith and Lance. In addition to his skills piloting human ships, Shiro was also a master pilot of the Black Lion. His bond with Black was so deep that Shiro was the only Paladin to pass the blind dive training exercise, thus allowing him to see through Black's senses and body. Shiro was also known to be among the most skilled in hand-to-hand combat among the Paladins. Shiro's lean and muscular build marks him as possessing incredible athletic abilities that allow him to rival even the likes of Hunk in terms of raw strength, and is able to duck and dodge with great agility and grace, rivaling Keith's speed, Pidge's balance, and Lance's precision. Shiro's greatest asset is his superb tactical mind and leadership skills, allowing him to take on stronger foes such as Myzax in both the gladiator pit and on Arus within Voltron. Shiro regularly and skillfully inspires his team with his charismatic personality and indomitable spirit and is able to bring them from the depths of defeat and ignite their will to win, thus allowing them to push back with the strength of a true army while acting as one. He is also skilled in military tactics, which is how he learned the guards' routines aboard the prison ship where he was held. Shiro is also skilled at reading the tactical weaknesses of others, devising plans based on their weak points, and often drawing out fights against stronger foes to learn any and all possible faults in their fighting styles and move sets.
- Shiro's scar has the same as Iruka from Naruto.
- Shiro is LGBT+ representation in the series, having had a lover on Earth named Adam. This was always intended to be part of his character, but his history had to be postponed due to scheduling and production. As far as his exact orientation, staff wrote him in such a way so as to leave room for interpretation. However, both Lauren Montgomery and Joshua Hamilton refer to Shiro as a gay man.
- At one point during early production, Shiro was intended to die during the second season. Staff did not want to kill off their gay character, so they were going to focus on a different character for LGBT+ representation instead up until they decided to keep Shiro alive and his story was rewritten.
- Shiro's birthday is on Leap Day (February 29), which only occurs once every 4 years. Leap Day birthdays are usually celebrated on the 28th on years that it does not occur.
- The black vest that Shiro sports in the first two seasons once belonged to Keith's father.