[2] Rin is reared as the successor to her family's magecraft, instructed by her father, Tokiomi Tohsaka, to prioritize sorcery over her own interests.

After her father is killed in the Fourth Holy Grail War, Rin continues to perfect her sorcery with some guidance from her guardian, Kirei Kotomine.

Several years later, she and Sakura observed a young Shirou Emiya attempting to jump over a high bar for a fitness test, and secretly found his dogged perseverance attractive.

Her character strives to earn the admiration of her peers to avoid drawing attention to her private life, even though she is secretly stingy, tomboyish, and a perfectionist.

In the original version of the Fate/stay night visual novel, written by Type-Moon founder Kinoko Nasu while studying at a high school, one of the opponents of the main protagonist Ayaka Sajyo was a ″princess type girl″, who was the master of Lancer.

However, after the protagonist's gender was changed and renamed as Shirou Emiya, Nasu and leading Type-Moon artist Takashi Takeuchi decided to completely rewrite the character of Lancer's master.

On the advice of Takeuchi, he decided to change her temperament to be similar to that of Aoko Aozaki, a character from his earlier novel, Mahoutsukai no Yoru.

To further define Rin's character, the screenwriter decided to give multiple sides to her personality, designing her as a beautiful woman who would be primarily cute and courageous while at other times swearing and acting aggressively.

After the release of Fate/stay night, Nasu felt that Rin had received the most complete character compared to the other heroes of the game and was his favourite heroine in the visual novel.

However, according to the writer, while writing scenes with Rin, he was under severe pressure from Takeuchi and other Type-Moon participants who placed greater emphasis on Saber and Rider.

"[5] In the making of the Unlimited Blade Works anime, Ufotable and Nasu agreed to keep her original looks from the visual novel believing it was still considered appealing.

[6] While designing Rin's visual appearance, Takashi Takeuchi worked with the goal of making her ″possess a sense of perfection and a surrounding atmosphere of inaccessibility″.

Takeuchi regarded Rin as a model student and therefore sought to draw a school uniform that would fit her better than any other female character of the game.

[8] In the Fate route as well as the first anime adaptation, after the encounter with Berserker, Rin suggests a temporary truce with Shirou to deal with the servant and his master.

In the True End of the route, she travels to England to stand trial at a kangaroo court for her actions in the Holy Grail War and later comes back to visit Shirou, Sakura, and Rider after she becomes the apprentice of the Wizard Marshall Zelretch, who saved her from prosecution at the last second.

[12] In the spinoff Fate/kaleid liner Prisma Illya, Rin is featured as a young sorceress sent by the wizard Kischur Zelretch Schweinorg to Japan in order to capture the Class Cards using the powers of a Magical Girl.

Though normally competent, her constant fighting with Luvia often causes them to create various embarrassing blunders, leaving Illya and Miyu with a negative opinion of their skills.

[13] Rin has appeared in the anime and manga versions of Fate/stay night, the movie Unlimited Blade Works (2010), and the ones from Heaven's Feel.

[18] In promoting the animated adaptations of Unlimited Blade Works, Rin was added to the game Summons Board and The Alchemist Code.

[43] Japanator stated that Archer's betrayal towards Rin felt like a sad twist due to how the duo originally made a major understanding in the previous episodes.