It's pretty late on in the night when there's some movement from the kitchen. He's not exactly trying to be quiet, things just lean that way for him.

Shay is currently checking the cupboards with one hand, hunting for a decent glass to drink from the bottle of rum in his other hand. He hears the party in the other room, but doesn't rightly feel social right now... He's also not going to inflict himself on the others having a good time.

So, rum-drinking alone, it is.