She made an apperance in Hayate no Gotoku! Chapter 1 and Episode 37 in the flashback when Ayumu asked Hayate if he can take a photo sticker with her, but had no involvement in the main story.
Ayu has long dark brown hair, dark gray eyes, wears glasses and is often seen wearing a Shiomi High School uniform.
In Heroes of the Sea Lifesavers, Ayu is usually seen wearing a two-piece swimsuit or various summer clothing.
On December 24th, while on their way to a Christmas party, Ayu, Hijiri and Souya, meet up with Hayate and try to invite him to come along, which he declines saying that he has no money and is on his part-time job. Much to their annoyance they start to question him about his dedication to work, which Hayate states his parents are unemployed. Afterwards Ayu and her friends leave ultimately feeling sorry for Hayate.