3rd and 4th Wheeling
Similar to 3rd wheeling but the only reason you don't have date of your own is that you're a fat ass thus counting as two people.
Boyfriend (To Girlfriend): Why is that fat girl following us around all the time?
Girlfriend (To Boyfriend): I'm sorry she's 3rd and 4th Wheeling but I felt bad that she was alone.
Girlfriend (To Boyfriend): I'm sorry she's 3rd and 4th Wheeling but I felt bad that she was alone.