Kou Ichinomiya is the son of a wealthy businessman who holds a firm belief in his elite status. As such, he is determined to avoid becoming indebted to anyone; but one day, after a run-in with some mischievous kids on Arakawa Bridge, he ends up falling into the river running underneath. Luckily for him, a passerby is there to save him—but now, he owes his life to this stranger! Angered by this, Kou insists on paying her back, but this may just be the worst deal the arrogant businessman has ever made. The stranger—a stoic, tracksuit-wearing homeless girl known only as Nino—lives in a cardboard box under the bridge and wants only one thing: to fall in love. Asking Kou to be her boyfriend, he has no choice but to accept, forcing him to move out of his comfortable home and start a new life under the bridge!

Yukito Kunisaki is on a journey in search of the Winged Maiden who was bound to the sky centuries ago, after hearing an old childhood tale from his mother. As Yukito shows his puppet show to people in an attempt to make some money, he finds himself in a small town in which he did not expect to stay very long. However, when he meets an unusual girl named Misuzu, things take a drastic turn as he is invited to stay with her. By staying in the quaint town, Yukito soon becomes friends with the locals. As he gets to know them better, he learns of their problems and decides to help, putting his search for the Winged Maiden on hold. With his search on hold, and his growing attachment to Misuzu and the small town, will Yukito ever find the Winged Maiden, or is she closer than he thought?

Throughout Shibuya, a series of murders dubbed the New Generation Madness gained widespread attention As these crimes gained infamy, they became a hot topic of discussion among the people of the area. Nonetheless, these New Gen murders do not capture the interest of Takumi Nishijou, a high school otaku who frequently experiences delusions and feels that he is constantly being watched. Having no concern for the real world, Takumi spends his time playing online games and watching anime. However, his ordinary life is disrupted when he receives a horrifying image of a man staked to a wall from a user named Shogun. After calming himself at an internet cafe, Takumi sees the exact same murder scene as the image portrayed happen right before his eyes, along with a pink-haired girl covered in blood calling out his name. Conflicted with the nature of reality, Takumi finds it difficult to judge where to place his trust as he gets caught up in the New Gen murders, believing that the murderer is out to get him.

After fainting at work, a young lady awakens in the back room of the café she works at with no memory of her life or those around her. Two of her friends, whom she soon learns are named Shin and Toma, are called to help her get home safely. Once she is alone, she meets a spectral boy named Orion that only she can see and hear. He explains that she lost her memories because of his chance visit to her world, so he vows to help her remember who she is. However, regaining her departed memories without worrying those around her may be more difficult than she realizes. In addition to the gloomy Shin and the protective Toma, she must be wary of arousing the suspicions of the captivating Ikki, the quick-witted Kent, and a mysterious man who lurks in the distance. As her amnesia entangles her in the lives of each of these men, her fragmented memories return piece by piece, and the mysteries of her circumstances slowly come to light.