You know, "May your soul rest in peace", "Wish your family the strength to bear your loss" and the like: sad messages at a time when words fail us all.
But if you page through the entire list of such messages (which I did when it was very much shorter than it is now), you will find one that is substantially different from the others. (Sorry, I don't know any way to point directly to it except for you to page through them all).
It reads "May I **** you in peace".
(That's a four-letter word familiar to all. It's not because I'm a prude that I've *-ed it out, but because the crude offensiveness of this message left me stunned).
Why would someone leave a message like that? I have no idea.
Who would leave a message like that? This person.
Update: Apparently I was wrong, I can point you to it. You can see the message in the middle of this page in Minal Panchal's scrapbook.