Still don't believe that glitter is the worst substance known to man? If so, I implore you to watch the above video that shows only a little glimpse of what it's like for someone to receive a tube of glitter unexpectedly. One *pop,* one "fuck" and one whole day/week/month ruined.
Here is it in GIF form, courtesy of Cooper Fleishman at The Daily Dot:
Don't send your enemies glitter, please. No one deserves it. But I guess also don't read your kids' mail, because they may have sent themselves glitter to mess with you. Lessons learned by everyone.