The slapstick comedy revolves around a protagonist who was reincarnated into a dummy head microphone (a microphone embedded in a fake human head to faithfully record the aural ambience). That dummy head microphone happens to be used by Yuri and other high school girls in an ASMR club, who have their sights set on the "ASMR Koushien" high school championships. (ASMR or Autonomous Sensory Meridian Response is the nerve-tingling or relaxing sensation one gets in response to stimuli such as certain sounds or sights.)<br>
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(Source: Anime News Network)

Aru Asa Dummy Head Mic ni Natteita Ore-kun no Jinsei