A master is out
A master is out was originally the caption to a picture posted to 2chan, of a dog shyly peeking out around a corner, implying in awkward grammar that the dog's master was out somewhere and thus the dog was waiting for them to return. It's possible that the translation was broken, and so the original message was actually along the lines of "Where did my master go?".
The picture in question spawned several photoshops, and the phrase was applied to several other pictures, eventually evolving on its own into phrases like "an insect is delicious" and "a photoshop is atrocious."