Aunt Pearl's Couch was a sofa that had been sitting in the attic for many years. It was owned by Pearl. Piper accidently blew up this couch as she was aiming for the Kazi Demon. Piper was blind at this time due to the Monkey Totem stealing her eye sight. [1]
Piper blows up the couch
The couch after the explosion
Phoebe annoyed that Piper blew it up