Race Spirit Aerial or Airy is the first Spirit summoned by Taichi Nishimura and becomes one of the main characters of the Isekai Cheat Magician series. Aerial has platinum green hair with teal colored eyes and pointed ears similar to an elf. She is shown to be wrapped in a green hagoromo like sash with four feathered wings sprouting from and wing like accessories in her hair and three diamond markings on both of her legs. She generally takes on the form of a young female fairy. Aerial is shown to be a very loving and caring spirit with a strong sense of duty and loyalty, despite the fact that she wished Tachi could have summoned her sooner so that she could help him, she could not disobey the conditions needed in order to summon her and feels both sad and regretful that she could not aid him when he needed it most in the beginning. Since her summoning she has done everything she can to be both helpful and useful to Tachi and is shown to be very loyal and protective of him, telling Tachi that she would never abandon him.

Spoiler

Originally she introduces herself as a simple Wind spirit named Aerial, but as Taichi's power rises, she finally evolves back into her original form, Sylpheed (Sylphy) her true identity.

(Source: Isekai Cheat Magician Wiki)