In Jay Asher’s novel Thirteen Reasons Why, Hannah Baker is a beautiful, seemingly popular teenage girl who dies by suicide, leaving behind a series of audiotapes for the people whom she believes contributed to her downward spiral.
Rising action refers to events in a story that lead up to the climax. Falling action, in contrast, refers to events that occur after the climax.
Since the novel begins with Hannah’s suicide already having happened, one could argue that her suicide is a part of the rising action.
However, I would suggest that it is actually part of the exposition. The exposition refers to facts of the narrative that a reader must know in order to understand what is happening in a story. Since few literary works start from the absolute beginning of a story, exposition is an essential part of the plot. In this novel, the exposition includes the knowledge that Hannah Baker has already killed herself by the time the story actually begins.