Once in Crystal, I went to heal at the Pokemon center. Then the Nurse Joy person said a really long speech. I thought "What? Well since she told me it doesn't do anything, I might as well keep it" and I did.
A while after that I got a DS and it fell, causing it to break. I had no idea that my Pearl game was still in there and my file was wiped clean.
Then, my brother was playing it and I saw his Pokemon had a small smiley face. I figured his Pokemon had caught the virus. I restarted the file and I saw some of my Pokemon had it. I still didn't know about EVs, so I didn't care.
A while after I learned about EVs, my Lapras had caught it and I wanted to spread it as quickly as I could so some box'd Pokemon that stay in there have it.
YAY FOR LONG STORIES. XD