"Why won't this city get destroyed..."

Chiho, a middle school girl teased for not having a smartphone goes to the seaside to vent her anger, there she meets the strange creature, Q!! Chiho takes a liking to Q, who feeds off human's negative emotions, then decides to secretly bring back and adopt Q, what mysteries does Q hold...?

Thus begins, in the port city of Numazu, the "invader life" of Chiho and Q.