I Just Killed a Bear

My roommate started to sing "Bohemian Rhapsody" after she got off of the phone with her

"Mamaaaaaaaaaaa."

I chimed in, "I just killed a bear/put a gun against his head/pulled my trigger now he's--"

"You just killed a what?"

"A bear...right?"

"Uh. I think it's a man."

So, I googled the lyrics, and yes, Freddy Mercury killed a man, not a bear. Why did I think it was a bear? And how, in my 23 years, did I not come to the conclusion on my own that he probably killed a man?

What song lyrics have you butchered?