The speaker is Death of the Endless, from Neil Gaiman's Sandman. The guy next to her is a Death Eater, from Harry Potter. You have to remember, when we originally post these Quickies, no one can see the title, so in order to get the joke, you have to know who they both are.
Death, by the way, is much smaller than the Death Eater. In order to make them look compatible, she's actually quite a bit closer to the camera, not to mention standing on a box.
Death: Why am I dating him? It's right there in his...
Death: See, his name implies...
Death: I mean, afterall, he IS a...
Death: ...well, let's just say I have my reasons and leave it at that.