A person not required, contributes nothing, excess to requirements. Full of their own self importance, always writes in the first party e.g. I build this, I've done that, I've bought that; regardless of how many others have helped or been involved.
Has to lie to cover inadequate knowledge on a subject.
A person lies and big notes themselves about something they had little to do with.
"You buckwit, you didn't do that"
Or "you buckwit, that's not true, here is the evidence"