Sora seems to be feeling better again. Last night, after I went to bed, he showed up and wanted to get under the covers with me, and snuggled and purred for a while before decamping to the heated cat bed. He spent the night there, and this morning went into the kitchen and chowed down on his food with gusto. I just went and found him (I had a migraine last night and am groggy from the meds, so working from home) sitting on the cat tree next to the window that looks out upon the bird feeder, and when I bent down next to him, he rubbed his head against mine and purred madly. So he seems to be much better.
He threw up yesterday afternoon, which he almost never does, before hiding himself away. We can only hope that he's gotten rid of the bug, whatever it is.
In other news, there's a new bird at the feeder! When I was messing with Sora, a black-capped chickadee flew up, perched on the feeder, took one look at me, and left. Black-capped chickadees were the most common bird at the feeder my parents had when I was growing up, and it's vaguley wigged me out that I hadn't ever seen any up here.