It had been two months. Two goddamn months since Dean had met Death. Thantos, Sam supposed. After all, it was rude not to call someone by their name. Anyway, Dean wouldn't tell Sam what had gone down, and that was worrying. Dean kept simply brushing him off with "You don't need to worry," and "It doesn't matter any more." He'd gotten more and more moody, and now, Sam could tell, he was near the breaking point.

"What's up, Dean?" Sam asked, looking over to where his brother gripped the steering wheel as if it had gravely offended him.

"And don't tell me it's nothing," he added, seeing Dean open his mouth, probably to snark at him. "I can tell something's wrong, so what is it?"

"Do you ever tire of having people's blood on your hands, Sammy?"

Well, that wasn't what Sam had expected.

"Of course I do," he answered honestly. "It's not something I can ever get used to."

"It's worse when it's a kid," Dean said, sounding strangely defeated. "And it's worse when it's their choice. When you can't do anything except hide in a back room and wait for it to be over."

"When did this happen?" Sam asked, though he was certain he already knew.

"With Death. He- he was willing to give me the ring, but he wanted something I couldn't give him for it."

Sam knew he would do better if he let his brother talk it out, but Dean seemed done, so he gave in to curiosity. "What?"

"He wanted me to promise that when you went to jump into the Cage, I wouldn't stop you. And I couldn't promise that. I swore that I'd die before I lost you again."

Dean sat quietly for a few minutes, focusing on the highway ahead of him.

"I said no. He reached out to kill me, but this kid grabbed his arm. He didn't die from the contact. He summoned Lucifer there and... I don't know. I was hiding like the coward I am. This is all that was left when I came out. This, and a set of scorched wing marks."

Dean held out a ring, silver with a skull design. Sam took it, turning it over and admiring the intricacy of the work. Tiny jet chips made the eye sockets. Despite being a ring, the skull looked disturbingly realistic. Sam almost expected it to move, but that was a silly fancy. Even in their business, dead skulls didn't move.

"What was his name, Dean?" Sam didn't know why it seemed so important.

"Nico. Nico di Angelo."

"Nice to see you again," a lazy voice said from the back seat. Dean jumped, nearly putting Baby in the ditch. Sam pulled a knife from under the seat.

"Nico?" Dean said incredulously.

Turning, Sam saw a boy in his teens, dark haired and eyed. He looked a bit roughed up, fresh and old scars crisscrossing his bare arms, a dark bruise spreading over his jaw. Dark circles were evident under his eyes, and the black sword at his feet looked as if it hadn't been properly cleaned after the last use.

"May I have my ring back?" The boy inquired mildly. "It has considerable sentimental value to me."

Sam passed the ring over, and the kid – Nico, Sam reminded himself – slid it onto one pale finger.

"How was Hell?" Dean asked, looking like he dreaded the answer.

Nico made a so-so gesture. "Still doesn't make Top 10 Vacation Spots, but running a bit smoother. I got the crossroads demon Crowley running the place. Was that a mistake?"

Dean shrugged, but didn't answer, so Sam replied. "As demons go, he's one of the better ones. I wouldn't trust him out of shotgun range, but he's an administrator type. He's likely to keep everything business, no personal grudges or anything like that."

"I also made a few rules. No making deals with people who don't know what they're doing, with people under the legal age of consent without the legal guardian's signed permission, or-" He broke off suddenly.

"Or?" Sam asked curiously.

"Or people trying to bring back their loved ones." Nico blurted.

Looking at his brother, Sam saw his jaw tighten, but Dean didn't speak for several long minutes, and when he did it was to ask, "I was wondering, when I met you you kept talking about your dad. Who..." He trailed off.

"It may come as a shock," Nico warned, "but Dad's most common name is Hades."

For the second time in one night, Dean almost became more familiar with the ditch than was comfortable.

Sam wasn't driving, so his shock was less problematic, but no less potent. "Hades?" he spluttered. "Like, the Greek god?"

"Yup. I think he might not actually exist in this world, but I'm really not sure."

"In this world. So there's others?"

"Many," Nico said calmly.

"But- how?" Sam asked, baffled.

"You want the full explanation, or the short version?" Nico queried.

"Uh, maybe the brief version?" Sam said tentatively.

"Well," Nico started, "basically there's hundreds, if not thousands of other worlds. Then there's the different planes of existence. This world has five: Earth, Hell, Heaven, Purgatory and the Empty. They all exist on different levels in the same place. Hell isn't literally an underground labyrinth, Heaven isn't literally a beautiful place in the sky. You following me?"

Sam nodded, even though he wasn't, not really.

"They're basically different universes. They're in the same place, at the same time, but someone in one plane can't touch, hear, or see the others. At least, not normally."

"So at any moment I could be standing inside a demon, or driving through an angel?" Dean asked, taking an interest in the conversation, much to Sam's surprise.

"Exactly. Some people can perceive the other planes. They're usually called "schizo" or "psychotic," but they're really seeing beyond what most humans can. Gods and angels can, too. Kind of like how angels see your soul, rather than your appearance."

"So, what, you're telling me that you're not from this world?" Sam asked, nearly hysterical. "Then, where's your world? What's it like?"

"It's just like this one, except, instead of your monsters and suchlike, we have the Greek gods and monsters. The planes are Earth, Hades, Olympus and-" he hesitated, "And Tartarus."

"Isn't that, like, the "Hell of Hells"?" Dean wondered.

"No. It- it's more like Purgatory, actually. Full of monsters." Nico's voice cracked. "I'm sorry. It's- hard to talk about. I spent some time there, a few centuries ago."

"A few centuries?" Sam asked. "How old are you?"

He hesitated. "Physically, I'm sixteen. I'm two years old in this world, but I've lived four hundred, fifty-seven years, total."

"How did you get here?" Dean was trying very hard to seem uninterested. "I mean, it can't be normal to be able to go from world to world."

"I can travel through shadows. You saw it, how I appeared in the back seat. When- when my boyfriend, Will, died, I tried to kill myself. I walked into the shadows with no particular destination in mind, but instead of dying, I came out in a different world. It was really weird, all these kids running around waving sticks- sorry, wands, around. Some dude called Voldemort killed me, and I woke up somewhere else. And so it went. I've been to dozens of worlds, but never the same one twice, so I can't go back to mine."

"Look, I'm sorry about your boyfriend," Sam said. "I know how hard it is."

Nico scowled and looked out the window. "Whatever. Even with all my cool "death-y" powers, I can't bring him back."

Sam and Dean both pretended not to notice Nico wiping away a few tears.

"Well," Dean said a little too loudly, "There's a burger joint up ahead. Anyone hungry?"

"Starving," Nico smiled.