A bet taken too far

My girlfriend, Lana, and I had found a book of spells in a box of books my grandparents had left me when they died. We both got a laugh as we read some of the spells, figuring it was a joke. As we came across a spell for a 24 hour gender swap, she laughed and said to me “Jeff, if this was real, I bet you couldn’t survive 24 hours as a woman”. “Challenge accepted”, I said and laughed back at her. She read the spell, and as it turns out it was real.