"When grandmother called and said we had an emergency coven meeting last night, I nearly flipped out. Steve had scored two tickets to the big concert and I really wanted to go. Fortunately I had a way to be in two places at once, I just needed a willing subject to transform into my doppelganger and go to the concert for me. Then tomorrow, I'd take all the memories and relive them myself.
My lab partner Bill, seemed the perfect choice. He owed me a favor, and offered to do the concert for me. So, I transformed him and sent him off on my date, while I went to take care of coven business.
The next day, Steve calls to thank me for the great sex after the concert. Apparently Bill decided to try out the temporary equipment and went all out as me. I tried calling him, but he has apparently skipped out.
Now I have a problem. I have a duplicate out there wearing my shape, who might get me into all kinds of trouble, and I'm not a good enough witch to hunt him down without help. Grandmother could do it, but she'll probably ground me for weeks. So do I give Bill a few days and hope he comes back, or do I fess up and take my medicine?
Who'd have thought that nerd would have the guts to ditch his old life and run off like that."