[[quoteright:249:http://static.tvtropes.org/pmwiki/pub/images/Mushiuta.jpg]]

In the near future, BondCreatures called "Mushi", insects, exist. They grant power to their host, but at the cost of the host's dreams. A war rages between the Mushibane, a group of Mushi hosts who fight for freedom, and the Special Environmental Conservation Executive Bureau (SECB), who seek to maintain TheMasquerade. In the midst of this war, Daisuke "Kakkou" Kusuriya, one of the SECB, meets with a girl named Shiika for the second time. They grow closer as the war continues.

Based on a series of LightNovels. A sister series of audio dramas, ''Mushi-Uta bug'', was included with the limited edition [=DVDs=].
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!!This show contains examples of:

* ArcWords: "What is your dream?"
* ArmCannon: The fully powered version of Daisuke's Mushi turns his entire arm into a blaster.
* BondCreatures: The Mushi
* CodeName: Members on both sides of the battle take on the name of their insect as a code name. The search for "Fuyuhotaru" is central to the plot.
* DoubleAgent: Minmin.
* IWantMyBelovedToBeHappy: Rina, in response to Shiika.
* IncrediblyObviousBug: In more ways than one. Minmin's power is to use insects for spying.
* InsideAComputerSystem: Asami's power manifests itself as this.
* InvincibleHero: It is explicitly stated that being the cockroach makes Daisuke the most powerful host ever known. Although, being invincible in combat doesn't prevent him from failing missions, nor all the bad things happening to him.
* LaResistance: The Mushibane.
* LoveMartyr: Minmin.
* LoveTriangle
* TheMasquerade
* TheMenInBlack: SECB.
* MysteriousWaif: Shiika.
* OurSoulsAreDifferent: One's Mushi is tied to one's dreams/soul, and if a person's Mushi is killed, they get LaserGuidedAmnesia and become TheHeartless. It ''is'' possible to regain their dreams, though.
* PostEpisodeTrailer: Playing off the Arc Words, each member of the cast describes their own dreams and tells the next episode's title. No actual content about the next episode included.
* SnowMeansDeath: Shiika [[spoiler:("Fuyuhotaru")]] invokes this trope in her battles.
* {{Technopath}}: C and Asami stand out the most.
* ThoseTwoGuys: Rina's three friends, one of whom (Asami) becomes important.
* TripleShifter: Rina, as both the leader of the Mushibane and a normal high school student.
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