Chummer
A type of person who is a proper loner,
sad twat, armed with pointless questions to gain attention and/or to gain friendship, only to piss off and
weird out the person(s) they are engaing in conversation with.
Basically a step up from a sex offender and a step down from a train spotter,
anorak the lot
.
Guy gets out of his car, with a folder full of the cars history and every little bit of work done to the vehicle....with receipts.
Office worker Brian spots this and says to co-worker
Antony "look at this
chummer"