Charlie says shut up you are not retiring because that means they are all getting old. Also because Oliver is too awesome to be retiring any time soon and he's not that much younger than Sean ;) He was a Gryffindor rather than Hufflepuff, but Charlie was (I think) good friends with Tonks, so was likely known to most of Hufflepuff!
Asher also says shut up you are a BABY. He has no plans to retire any time soon. He will keep playing until his arms fall off, apparently. ;) He's played against Sean for years, so probably knows him pretty well, at least in a professional sense.
Pansy doesn't know him, she doesn't really pay attention to quidditch. Sorry Sean.
Remus also doesn't know him particularly, again he doesn't pay much attention to Quidditch at all, other than when the Potters force him to pay attention.