Betty (The Stray)

From Tardis Wiki, the free Doctor Who reference

Betty was an old woman who lived by herself. She took in a stray which she believed was a Yorkshire Terrier and named it Pookie, but it was actually a Kera-Bera Beast that began feeding off of her energy, causing her health to begin to suffer. Without her awareness, the Eleventh Doctor and Amy Pond used a converted hairdryer at Betty’s local salon to break the beast's influence and pacify it into believing it really was a Yorkshire Terrier. (DWA: The Stray)