Sayaka Ichinose is the main antagonist of the hentai OVA series "Cleavage". She is Yuuto Toudou's art teacher and second love interest. Throughout the series she causes relationship problems between him and his stepsister/first love interest Erika Toudou. She blackmails and seduces Yuuto into having affairs with her.

Ichinose is often described by a lot of male students as an exotic beauty. She has Red hair, wears glasses, has teal green eyes, and fair skin, her outfits vary but her attire always appears to be skimpy or sexually arousing. Her most noticeable trait are her enormous breast of which she has the largest size out of anyone else in the series, even surpassing Erika.

Ichinose is a mature woman with a fine amount of patience. She treats her students with respect and care. However she is also very seductive and persuasive with a slightly devious nature when it comes to getting things she wants as she mostly resorts to using any forms of blackmail and sexual harassment on her students in order to give herself extreme pleasure and satisfaction.

(Source: Fictional Characters Wiki)