Nao, a high school girl living a self-proclaimed "normal" life, is one day approached by her mysterious classmate Kiri in the school library. Kiri invites Nao to come with her to visit a scene of a murder in Kiri's neighborhood which she's using as inspiration to write a novel. Meanwhile, sisters Baeru and Kei, witness their father being beaten by someone on their moutain cottage. The sister flee, only to be chased by the attacker. Kotone, works at a coffee shop run by her father, after failing the entrance exam for music college. She works with her childhood friend Kazushi, and the atmosphere in pleasent. Her younger sister Kanon, is worried about Kotone, but spends her days devoted to her band. A mysterious girl stands on her balcony in the rain. What is beyond the gate that looks at? These four stories will intersect, as the boundaries between each girl gradually become borderless... ~~ Adapted from the novel "Borderless" by Tetsuya Honda.