Watashitome

SHION KYOUGA , a first-year high school boy who follows a simple concept of "TO NOT HURT ANYONE'S FEELING " , has end up making himself not to talk anyone which further leads to social anxiety in him.
As our boy's life was going on.
One day he wakes up and found himself laughing loudly in front of a mirror , he thought it was a dream and pinched himself but this was a start of nightmare. SHION'S mouth moved automatically without his control and said , HELLO , SHION KYOUGA , I am x , and I am controlling your body , I am here to destroy you . SHION scared and don't know what to do.

Who is this x person ?
Why does it want to destroy SHION ?
How this x person gets into our boy's body ?
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