How does the author use allusion in the novel, What If It’s Us?

The author uses allusion to Harry Potter to indicate difficulties with which characters struggle. Many references to the book series are made throughout this story, both in characters' actions and in their thoughts. Arthur awards twenty points to Gryffindor when he manages to talk to Ben. Dylan argues with Ben over which character they would be if Samantha were Hermione. The cover of Ben's novel originally was designed modeled off of Harry Potter book covers, but it's not quite right. The day that Ben has his biggest fight with Dylan is Harry Potter's birthday.