~Rin Itoshi~

Rin is Sae Itoshi's younger brother, who started playing soccer with him at a young age. He played as a striker in every team he played for, and was always considered one of the best players. He is considered the best player in Blue Lock. Rin's main goal is to become the best striker in the world. He used to be fixated on beating his brother in soccer and in turn taking revenge for their shared dream being abandoned, but after Blue Lock Eleven played against the Japan U-20 team, he gave up on his revenge and decided to change himself to become the best striker in the world, defeating everyone in his path. Rin is a tall teenager with a slender yet muscular build. He has black hair with bangs that fall more over his right eye than his left, narrow turquoise eyes, and defined eyelashes that he shares with his brother, Sae Itoshi. Sae is a tall, thin young man with purple hair and thin turquoise eyes framed by long eyelashes, much like his brother, Rin. From a young age, Sae was cold, straightforward, and serious. He only ever cared about becoming the best striker in the world, and only had time for things that would get him closer to his goal. Sae can also be arrogant and condescending, looking down on others even if they are older than him and have greater organizational authority.

As a child, Rin was very innocent and in awe of his brother, Sae, wanting nothing more than to become as cool and strong a player as he was. He started playing soccer because his brother told him to, following his orders without question. When they played soccer together, Rin would listen to everything Sae said and adjust accordingly. When Sae left for Spain, Rin found it harder to play soccer without his brother, but he aspired to become like him and replace him. Initially, he was a good team player and captain of his middle school team, and seemed to have good relationships with some of his teammates. However, due to a falling out with his brother, he became cold, blunt, and overly serious. He is completely focused on soccer, almost to the point of obsession, and is also very selfish, as he always puts his goals above everyone else and their motivations. Rin has a great deal of pride as a striker, bordering on arrogance, as he often describes soccer and other people's mindsets as "sluggish" or "mediocre". These mannerisms and behaviors are inherited from his brother; in an attempt to be like his brother, Rin copies his words and embodies his mindset.

Tourette syndrome is a disease in which a person has uncontrollable motor tics and behavioral disorders. The pathology is related to disorders of neuropsychiatric origin. The anomaly is accompanied by hyperkinesis, shouting, increased activity. The person is unable to control himself, so the manifestations occur spontaneously.