Where does the 11 reputation for this member come from?
Judging from the answer downvote, it appears as if he started with 13 reputation which makes no sense..
It's not accepted suggested edit, his activity is clean.
The user does have an upvote - see the reputation tab
The upvote doesn't show on the info page as there is 2 x downvotes to one upvote
You can't get less than 1 rep, so user started off with 1, - and it stayed at 1 after the 2 x downvotes, then yesterday they got an upvote of 10 + 1 = 11
not sure if retro backvotes recalculate rep in a case like this though?