Necessity

"You saw the news, Brian.  That bus is about to plummet off the Golden Gate Bridge. There are forty children aboard. You're the only one with the powers to save them."

"Dude, I can't believe you used your only wish to turn me into a chick..."

"I wasn't trying to! All I said was 'I wish there were a superhero here who could save those kids.' How was I to know that you would become Wonder Woman?"

"Well, you have me over a barrel. After I save those kids, I'm coming back here. And if I'm still mad, I'm going to put you over my knee."