In the book Understanding Manga and Anime, writer Robin E. Brenner states that while Western readers have previously seen Subaru and Seishiro's dysfunctional relationship in other series, it stands out because Western authors tend to avoid portraying homosexual relationships. He referred as well to Subaru's and Seishiro's relationship as one of the most explicit ones from X. However, regarding his role in Rintaro's 1996 movie of X, Ex criticized his lack of appearances as he and Seishiro are killed quickly. The character's inclusion in Tsubasa: Reservoir Chronicle was well received by Sakura Eries from The Fandom Post. She elaborated that the use of Kamui and Subaru as vampires is well executed and with their help, Fai D. Flowright survives his blood loss after Syaoran takes his eye, becoming a vampire to survive. Like other critics, the writer wondered when Clamp would explore his past.
