Weird name in user permissions list

I had opened up my drive security properties to check something and there is this user account (*computer-name\blfyrruwtb) <-doesnt seem legit in the permissions tab. The account does not appear in the C:\users list nor the user account list. However, it appears as a user under a search under user domain on the pc (other users are my account, admin and guest). recent malware and rootkit scans had turned up clean. Can someone help with the issue?