In my view, if you smell any kind of happening or misbehavior, REPORT and BLOCK that user ASAP. IMVU helps in blocking them and deleting their accounts.
Also, don't share much details about yourself to an unknown "user" in your friend list. It depends on us about how much we give information 'bout ourself.
Also, the biggest problem is the credits. I know we want to buy many stuffs from the shop. And many fishers and spammers uses this to get our account info. So NEVER NEVER trust anyone who says they will give you credits or blah blah.
Check this topic to know some known and unknown ways to earn IMVU credits.
https://www.imvumafias.org/community/viewtopic.php?p=163231#p163231