Sean posted the full text of his story, "Masks", over on his blog. I've done a review of it.
As always, Sean displays his trademark smooth writing and deft world-building. I'm guessing that this is an Antaria story, but even if I wasn't aware of that creation, I would have no trouble imagining the world he's describing from the details. The dialogue shows enough characterization to differentiate one person from another without too much description. These are enviable strengths, and these are what draw me into the story.
However, as a reader, I found my interest waning steadily somewhere in the middle of the encounter with Lord Polonius. There's a hint of intrigue, but at that point, I start to wonder whether it will actually lead to anything. A lot of information, especially the narrator's opinions about masks, is repeated, but I don't feel any buildup of tension.
This lack of buildup brings the ending as a total surprise. Masterfully done, I must admit, because it evokes shock. But I found myself asking: "Where did that come from?" It may be in line with Sean's concept of masks hiding purpose, but it hides the purpose even from me, the reader.
When the end comes to the point that it does, I don't have enough emotional investment in the characters to feel anger or pity or sadness. It's just a rude shock.
All this is from a first reading. I'll revisit it again sometime and see if I hold the same opinion.