Sometimes users on Whisper (or maybe even the Whisper Team themselves) will flag or report posts, and they often get deleted pretty quickly.
One thing I will say is that this "reporting system" seems to be inconsistent... I've seen some pretty shocking things on Whisper that have avoided deletion, while some seemingly innocuous messages get dealt with quite harshly.
If you feel like you've been hard-done by, I'd suggest contacting Whisper via Twitter: https://twitter.com/Whisper
From my experience, they take complaints quite seriously!
