
Piper Willis, played by Mavournee Hazel, made her first screen appearance on September 16, 2015. The character has often been mentioned since the arrival of her on-screen family in May 2013, while Hazel's casting was announced on August 18, 2015.
The actress relocated to Melbourne for filming and commented "It's a great feeling to be rewarded with the role of Piper after years of hard work, especially when I fell in love with the character after my first audition." Ahead of her first appearance, the character was featured in a series of webisodes titled Hey Piper, which see her talking to her family via online video calls.
Piper is the youngest daughter of Brad (Kip Gamblin) and Terese Willis (Rebekah Elmaloglou). She has been away studying in Canada. Hazel stated that she and the producers had a similar idea of how they wanted the character to be, and she was billed as being "feisty" and "quirky". In an interview with Carena Crawford from All About Soap, Hazel described Piper as "a technology-loving, free-thinking, liberated teenager". She also said she was mature and intelligent, but unlike her sister Imogen (Ariel Kaplan) she likes to discover things for herself. Piper struggled to "find her own light" growing up with Imogen and Josh (Harley Bonner), and before she went to Canada she did not have a strong identity. Hazel added that Piper does not want to be forced into taking side in her parent's separation.
Piper arrives home from Canada during the middle of a family argument. The following day, she asks Lauren Turner (Kate Kendall) for advice on bus fare, initially unaware that she is the woman her father had an affair with, until they are introduced. She also meets her half-sister Paige (Olympia Valance) in person for the first time. While updating her vlog, Piper befriends Ben Kirk (Felix Mallard) and they spend the day together. Piper receives texts from her ex-boyfriend Chas, and accuses Imogen of not knowing her anymore, as she has changed while she was away. When Brad reveals that he is going to be moving in with Lauren, Imogen makes Piper and Josh promise not to visit him there. However, Piper breaks the pact, causing an argument between her and Imogen. Piper begins to feel isolated from her family and when they present her with a memories jar, she deliberately smashes it. Ben returns to Erinsborough and Piper berates him for spending time with his ex-girlfriend, who posted his nude pictures online. Piper later opens up to Ben about her ex-boyfriend, who she broke up with before she left Canada. Ben and Piper escape a fire at Erinsborough High with minor smoke inhalation, but Terese needs a skin graft after she is badly burned. Piper pushes Brad away when it emerges he saved Lauren first. When Ben confesses to starting the fire, Piper admits to Lauren she encouraged Ben to set the sprinklers off as a joke. Scared of how her family will react, Piper tells Ben she is running away and he decides to go with her. They stay in a motel in Glenrowan and find jobs as fruit pickers to earn money to get to Sydney. Piper later calls Terese to tell her that she is okay. When Ben collapses in pain due to fractured ribs, Piper sends him to the hospital in a taxi. Her parents then arrive to take her back home.
Piper turns to Tyler Brennan (Travis Burns) for advice about her first day back at school and he tells to own her mistake. After enduring the other students calling her names all day, Piper takes a lighter and threatens to set to fire to something. Terese bans Piper from social media. The ban is extended when she posts online a disparaging advertisement about Fitzgerald Motors. Piper begins a romance with Tyler but when seen picking petals from a daisy she says she is in love with a boy at school. Josh discovers that Piper is in love with Tyler. Later Terese finds out and bars Piper from working at the garage. Piper befriends Xanthe Canning (Lilly Van der Meer) and has to keep her out of trouble, when her various moneymaking schemes get her on the wrong side of the law and her grandmother Sheila (Colette Mann). Piper's ex-boyfriend, Brodie Chaswick (Matt Testro), asks Brad to coach him again and he moves into Number 22. Piper and Brodie resume their relationship in secret, until Josh catches them kissing. Piper and Brodie then tell Brad and Terese, who suggest Brodie moves out, but they change their mind. After Brad stops coaching Brodie because of poor form, Brodie and Piper leave together for Perth but Piper changes her mind and calls Tyler to collect her. After the hotel explosion which killed Josh, Piper and Ned are going through Josh's belongings, when Ned reveals that he is a tattooist. Piper has Ned put a tattoo on the left hand side of her stomach to remind her of Josh, despite Brad's disapproval. Piper begins to suspect that her ex-boyfriend, Brodie, may have caused the explosion. She questions him and he produces plane tickets which provide him with an alibi. Love grows between Piper and Tyler, but Terese won't approve because of the age difference between them. Terese agrees to allow Tyler to go to the formal together on strict conditions but changes her mind when she hears them planning to sneak out and have sex. Piper sees Tyler with a strange woman in the pub and throws a drink on her. Tyler tells Piper that their relationship is over. Piper learns that this strange woman is Susan's niece, Elly Conway, and will be Piper's new English teacher. Piper finds a stray cat and her mother at first won't let her have it in the house, but is later persuaded to change her mind. After Piper and Ben work together on a film project, Elly gives Ben a higher mark, whereupon Piper thinks that Elly is dishonestly marking her down.