The series follows researcher/landlord Kasane Himesaki, and her young assistant Kon Wataya, a 2nd year student at Ui Municipal Middle School, through their life in a world filled with "Exceptional Phenomena" (a.k.a "Bugs"), spontaneously-occurring phenomena that can range from slight changes to the world, to the appearance of mysterious creatures, and even to the alteration of fundamental laws of nature. Kasane is a researcher of these bugs, and the landlord of a share house, where Kon lives with her and three other occupants; the lively Kousei Ishibashi, the quiet Akira Iyoda and the hard-working Asuka Maruko. With all of these people around him, Kon knows that each day will be interesting!