When Rumiko Takahashi began the series, the only ideas she had were Inuyasha being sealed by Kikyō and his sword being a relic from his father, everything after that was thought up on a weekly basis.

Inuyasha's appearance is a mixture of his dog demon father and human mother: he has his father's long silver hair, yellow eyes, and claws, but does not exhibit facial markings in his half-breed form, or pointed humanoid ears, instead he has a unique pair of furry silver dog ears on top his head.

As a dog demon, Inuyasha has claws he uses to fight with, utilized mainly in his Sankon Tessō (散魂鉄爪, "Iron Reaver Soul Stealer" in English) attack.

Although a half-breed, a hanyō, Inuyasha's strong demon heritage inherited from his father affords him supernatural physical attributes and resilience; he possesses raw strength as well as speed and reflexes considerably superior to that of all lower-level and the majority of middle or even higher-level yōkai.

His durability and regenerative abilities are similar to those of yōkai and allow him to endure severe pain and recover quickly from wounds as well as extending his lifespan by hundreds of years.

Due to his half-breed blood, Inuyasha temporarily loses all his demon traits and powers on the night of a new moon, effectively becoming completely human.

Born to a dog-demon father and a human mother, Inuyasha is a dog demon/human hybrid who initially wanted to use the enormous power of the Shikon Jewel to become a full-fledged demon.

[10] In a review of the second manga volume, Megan Lavey from Mania Beyond Entertainment commented that the character's development was depicted for the first time as the story began to explore why Inuyasha is often angry and has difficulty trusting others.

[13] Similarly, Holly Ellingwood from Active Anime particularly enjoyed the comedy that occurs when Inuyasha visits the modern world following Kagome.

[15] Anime News Network felt the character became a less interesting anti-hero as the plot progressed and criticized the handling of his dynamic with Kagome due to the repetitive romantic tension despite both often arguing.

[17] Briana Lawerence from Mania Entertainment was harsher in regards to these situation as the narrative continuously focused on this triangle for multiple seasons, leaving her the desire for Inuyasha to decide a love interest because she found the character annoying as a result.

[18] In her book Anime from Akira to Howl's Moving Castle, scholar Susan J. Napier analysed how certain lessons in the series relate to Inuyasha's representation of masculinity.

[20] IGN's D. F. Smith praised the voice acting of Richard Cox as "he does a fine job getting the character's rough-edged, angry mode of speech across, even without being able to stick "yarou" at the end of every sentence.