It took Ryan about a week to come up with a perfect plan to get his body back from Melissa. He cast the spell again, but this time he didn't even attempt to kiss Melissa in his old body. In fact, she wasn't even nearby. He opted instead to kiss a random stranger. Switching bodies with this woman would give him another three tries to get it right. Plus, Melissa was probably expecting to see her own body try to switch back with her, not some random stranger.