Long story...here's the short version. My friend wrote a HUGE story about my dog named missy. In order for the story to be interesting Missy was too wussy of a name so he changed it to Mizzy. Basically, the anti-Mizzy came along called Yzzim and did all this hilarious stuff to the stupid dog which I laughed my ass off at. So, the name stuck. Have had this name since I first got on the internet back in 1994.
Oh, my friend wrote the story when we were in 5th or 6th grade, so writing stories about some dogs beating other dogs was some pretty funny stuff.