Maybe the content didn't have a proper copyright:
From the Fanpop Terms and Services:
link - anda understand and agree that Fanpop may review and padam any Content (Fanpop, links, images, profiles, comments, postings, messages) that in the sole judgment of Fanpop violates these Terms of Service atau which might be offensive, illegal, atau that might violate the rights of, harm, atau threaten the safety of other users atau members of the Fanpop Site and/or other website users.
- anda may not post, distribute, atau reproduce in any way any copyrighted material, trademarks, atau other proprietary information without obtaining the prior written consent of the owner of such proprietary rights.
Also, did any of the content fit this criteria:
The following is a partial senarai of the kind of Content and communications that are illegal atau prohibited on/through the Fanpop Site. Fanpop reserves the right to investigate and take appropriate legal action in its sole discretion against anyone who violates this provision, including without limitation, removing the offending communication from the Fanpop Service and terminating the membership of such violators atau blocking your use of the Fanpop Service and/or Fanpop Site. anda may not post Content that:
is false atau intentionally misleading;
- is patently offensive to users of the Fanpop Site, such as Content atau messages that promotes racism, bigotry, hatred atau physical harm of any kind against any group atau individual;
- harasses atau advocates harassment of another person;
- involves the transmission of unsolicited mass mailing atau "spamming";
promotes illegal activities atau conduct that is abusive;
- is threatening, obscene, defamatory atau libelous;
- is pornographic atau sexually explicit in nature; and
seeks atau recommends providers of material that exploits people under the age of 18 in a sexual atau violent manner, atau seeks atau recommends providers that solicit personal information from anyone under 18.
If anda were not notified of the reason for the removal in a e-mail atau other, then anda should probably notify the Owners of Fanpop. It may be a mistake.