Fluttershy has always wanted to give more of her kindness towards ponies. However, her shyness impedes her speaking, which makes her hard to express herself. After asking for her help, Pinkie Pie teaches Fluttershy to communicate with physical interactions instead, like hugs.
It works so well that Fluttershy decides to hug every pony in Ponyville.
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Written with the single goal to create the cutest, most heartwarming short story I can imagine (without going romance).