From the discussion over the last few days, it may seem that despite my initial mention of it, I have chosen to disregard the possibility that some sort of trickster deity had something to do with my shirts' disappearance. This isn't exactly so.
It is very hard to speak comfortably of an immortal's activities on our plane of existence, since in all but the rarest, most extraordinary cases, deities assert their agency via subtle influence rather than direct action. It wouldn't be inaccurate to say that a person (or other physical force) becomes the agent for the deity's whims. But how, then, do you differentiate divine influence from that agent's more prosaic activities? Given our rather impoverished perceptual abilities (by the standards of the vast panoply of beings whose planes ever intersect our own, anyway), it's rarely cut-and-dried.
Imagine, for example, that you are reading a book that you are really enjoying. You're moving towards the climax, and the book's momentum is really picking up. You realize you're thirsty, so you decide to take a little break to go get a beverage before moving boldly toward the book's exciting finish. You set the book on the side table next to the lamp, and go get your beverage. When you bring the glass back, you realize you need to use the restroom, so you put the glass down next to the book. When you return, you discover that the cat has jumped onto the side table and knocked your glass over. Now the book is soaked. "Damn it!" you cry. "Stupid cat!" To our haughtily incredulous, post-modern world-view, that's the end of the story: the cat was naughty. But can you really comfortably say that the cat wasn't in some way compelled into that action?
Indeed, it is perhaps worth asking: Don't the cat's weird, almost alien whims ever make you wonder just what the hell is going on in its furry, befanged little head? Can you really be sure it isn't some kind of antenna for the eldritch impulses of supernatural entities? And thus the follow up question: Why do you even have a cat in the first place? Why didn't you just get another dog?