Board Thread:Questions and Answers/@comment-88.193.168.163-20150815115548/@comment-3250527-20150826201445

Here, it probably signifies a type of mockery, similar to the derogative 'ki-sama'. Originally, '-sama' is to show great recognition and show a large amount of politeness, but this certain pronoun uses it like the form of "oh, great high and mighty".

Kirito is likely being referred to as a know-it-all gamer, AKA, no-life on top of his black wear.