Sayo Hayakawa is a Japanese fashion model. She is best known for her stint as a main model for the Koakuma Ageha cabaret-gyaru fashion magazine.

Koakuma Ageha is Japanese magazine that introduces the latest fashion and lifestyle trends popular among hostesses that is published twice a year, with the main target audience being women in their teens to 20s. Fans of the magazine are also referred to as "agejo" and often members of the Gyaru subculture.