One day, suddenly mysterious Aliens enter into human brains through the ear canal, taking complete control of their bodies. one targets Shinichi Izumi's brain, however due to his headphones. he is unable to enter his brain and ends up taking control of his right hand. since it was on his right hand (migi te) he decided to call it Migi, [right in Japanese] Accepting the fact that one would die if another dies, they join forces against other parasites.

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