To perform oral sex on a woman. So called because from a womans perspective whilst having oral sex performed on her the other player would resemble Stalin, WW2 Russian dictator renowned for his bushy moustache.
Okay love, before we get down to a bit of the old heave-ho i though i'd just nip downstairs and do a quick impersonation of stalin, just to sayi love you.
When your being awkward around a girl on a date so when you or her mentions it you say "thats my (insert name of someone whos realy awkward around girls or was once) impersontation"
Character impersonation syndrome or echopraxia is when a person is imitating or copying another human or fictional character. The things they are copying can vary from emotions, movements or even dialects or speech.