A sockpuppet is an online identity used for purposes of deception. The term, a reference to the manipulation of a simple hand puppet made from a sock, originally referred to a false identity assumed by a member of an Internet community who spoke to, or about, themselves while pretending to be another person
Lara I did as you suggested and contacted HQ last week about this very issue, giving reasons for my suspicions, including having received some very bizarre PMs, which led me to believe there was a poster with multiple user names.
The reply I received, said that there was no issue and if I received any more disingenuous PMs to let HQ know.
The events of today have made me wonder if my suspicions were not unfounded after all.
I hate to see vulnerable posters being taken in and spun a yarn.