A shadow of Darkness approaches a peaceful Forest... Sounds like trouble for Mushiking! Lets put our strengths together and fight Adder! Deep in the Forest exists a paradise for the fairies and insects. There, Popo the Fairy, Mushiking, The King of Beetles, and many other beetles live happily together. One day, a happy-go-lucky beetle named Iron Stripe Stag-Beetle (Iron Stripe) from another forest appears in front of Popo, requesting a challenge with Mushiking in a combat. Suddenly, Iron Stripe and Popo are attacked by a red-eyed beetle, Blue Hercules Beetle, who is being controlled by Adder, the Fairy of Darkness scheming to rule the Forest. Mushiking, The King of Beetles, rushes to the rescue, but with Giraffe Stag-beetle (Giraffe), also controlled by Adder, showing up, he has to battle two giant beetles as he defends Popo and friends, and gradually losing strength, gets captured and is taken away.

One night, Mikado Ryuugamine accepts an invitation to Shinra Kishitani's apartment, eager to talk to Celty as quite some time has passed since the two last spoke. But, much to his astonishment, he finds that a large group of Ikebukuro's finest has gathered there for a hot pot party. Already confused with the current situation, Mikado is further surprised to see that his friend and fellow Raira Academy student Anri Sonohara is there as well. As the two decide to take a seat together, a few members of the group begin reminiscing over events from days past: Mikado recalls an adventure from his childhood with Masaomi Kida, Anri explains how she came to be friends with Mika Harima, and Shizuo Heiwajima tells of his first meeting with Tom Tanaka.

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]

Zenitendo is a mysterious candy store that only lucky people can reach. All the candy recommended by Beniko, the owner of the store, is perfectly suited to the buyer's troubles. However, it depends on whether the candy will be used or eaten correctly that it can bring happiness or misfortune.