one black eye looks a little lonely

I found the following conversation from a TV show “Gossip Girl”.

Chuck: This isn’t over!
Dan: Hey, anytime man. That one black eye looks a little lonely.

I don’t 100% know how to interpret the quote that Dan said though it doesn’t interrupt me from understanding the whole scene, can anyone help me to understand and interpret it properly? also, why use ‘one black eye’ instead of ‘two black eyes’ as we all have 2 eyes… what is little lonely btw?

thanks for helping ^^

Hi runs,

If you’ve got a ‘black eye’, then the tissue and skin around the eye is discolored as the result of bruising from damage received. Often these bruises turn a dark nasty blackish purple color, so we call them ‘black eyes’.

In the conversation above, Chuck has a black eye, and when Dan says it looks ‘a little lonely’ Dan is offering to give Chuck another black eye to balance them out, or to keep them company. (The idea is that something by itself is lonely).

Dan is being very sarcastic, offering to ‘help’ Chuck. Since Chris makes the statement “This (argument) isn’t over” it’s clear that Chuck and Dan have been fighting, at least verbally if not physically. It was probably Dan who hit Chuck in the face causing the 1st black eye, and now he’s suggesting that if Chuck wants to continue the argument, then he’ll ‘help’ him by giving him another bruised eye.