"Mushi": the most basic forms of life in the world. They exist without any goals or purposes aside from simply "being." They are beyond the shackles of the words "good" and "evil." Mushi can exist in countless forms and are capable of mimicking things from the natural world such as plants, diseases, and even phenomena like rainbows. This is, however, just a vague definition of these entities that inhabit the vibrant world of Mushishi, as to even call them a form of life would be an oversimplification. Detailed information on Mushi is scarce because the majority of humans are unaware of their existence. So what are Mushi and why do they exist? This is the question that a "Mushishi," Ginko, ponders constantly. Mushishi are those who research Mushi in hopes of understanding their place in the world's hierarchy of life. Ginko chases rumors of occurrences that could be tied to Mushi, all for the sake of finding an answer. It could, after all, lead to the meaning of life itself. [Written by MAL Rewrite]

On a rainy morning in Tokyo, Takao Akizuki, an aspiring shoemaker, decides to skip class to sketch designs in a beautiful garden. This is where he meets Yukari Yukino, a beautiful yet mysterious woman, for the very first time. Offering to make her new shoes, Takao continues to meet with Yukari throughout the rainy season, and without even realizing it, the two are able to alleviate the worries hidden in their hearts just by being with each other. However, their personal struggles have not disappeared completely, and as the end of the rainy season approaches, their relationship will be put to the test. [Written by MAL Rewrite]

As Kobayashi sets off for another day at work, she opens her apartment door only to be met by an unusually frightening sight—the head of a dragon, staring at her from across the balcony. The dragon immediately transforms into a cute, busty, and energetic young girl dressed in a maid outfit, introducing herself as Tooru. It turns out that the stoic programmer had come across the dragon the previous night on a drunken excursion to the mountains, and since the mythical beast had nowhere else to go, she had offered the creature a place to stay in her home. Thus, Tooru had arrived to cash in on the offer, ready to repay her savior's kindness by working as her personal maidservant. Though deeply regretful of her words and hesitant to follow through on her promise, a mix of guilt and Tooru's incredible dragon abilities convinces Kobayashi to take the girl in. Despite being extremely efficient at her job, the maid's unorthodox methods of housekeeping often end up horrifying Kobayashi and at times bring more trouble than help. Furthermore, the circumstances behind the dragon's arrival on Earth seem to be much more complicated than at first glance, as Tooru bears some heavy emotions and painful memories. To top it all off, Tooru's presence ends up attracting several other mythical beings to her new home, bringing in a host of eccentric personalities. Although Kobayashi makes her best effort to handle the crazy situation that she has found herself in, nothing has prepared her for this new life with a dragon maid. [Written by MAL Rewrite]

Mirai Kuriyama is the sole survivor of a clan of Spirit World warriors with the power to employ their blood as weapons. As such, Mirai is tasked with hunting down and killing "youmu"—creatures said to be the manifestation of negative human emotions. One day, while deep in thought on the school roof, Mirai comes across Akihito Kanbara, a rare half-breed of youmu in human form. In a panicked state, she plunges her blood saber into him only to realize that he's an immortal being. From then on, the two form an impromptu friendship that revolves around Mirai constantly trying to kill Akihito, in an effort to boost her own wavering confidence as a Spirit World warrior. Eventually, Akihito also manages to convince her to join the Literary Club, which houses two other powerful Spirit World warriors, Hiroomi and Mitsuki Nase. As the group's bond strengthens, however, so does the tenacity of the youmu around them. Their misadventures will soon turn into a fight for survival as the inevitable release of the most powerful youmu, Beyond the Boundary, approaches. [Written by MAL Rewrite]