A/N: This is a sequel to Boyfriend. It will really only make sense if you're read that first.

Arthur was dreaming. He had to be dreaming. There was no possible way his most trusted knight of Camelot, Sir Leon, was standing in front of him in the twenty-first century in Merlin's bedroom. He pinched his arm.

Leon was still there and now so was Merlin.

"Arthur, um, sorry about this. He just kinda rushed past me." Merlin tugged on Leon's arm, "Come on, let's let him go back sleep."

Leon brushed Merlin off and took a few steps towards Arthur dropping to his knees besides the bed. He bowed his head, "Sire! You came back! I don't believe it … You've actually come back!" He looked up at Arthur, "My king, my loyalty to you remains the same as always. I live to serve the Once and Future King."

Arthur stared mouth gaping and eyes wide. After a moment he looked over to Merlin, "What is this?"

Merlin twiddled his thumbs nervously, "So, there's still a lot I haven't told you about the time you were gone. Leon here is sort of in a similar situation to me …"

Leon's head snapped back towards Merlin, "You didn't tell him about me?!"

"I hadn't gotten around to it."

"You hadn't gotten around to it?"

"I was trying not to overwhelm him!"

"Well you've gone and messed that up now, haven't you?"

Merlin's face slowly became red as he yelled, "Me?! You're the one who barged right in when I told you not to!"

"I didn't think he was actually here!"

"You never think he's actually here! You always just think I'm off my rocker!"

"Because you always are off your rocker! It's never actually been him before!"

"I am not off my rocker!"

"You made us check out the Loche Ness monster, because you thought 'maybe he forgot which lake he was 'sposed to come out of and that he was 'sposed to have a human body and not be a sea monster'!"

"It was worth checking!"

"No, it wasn't!"

Arthur's head spun with the yelling and the shock of Leon being here. Suddenly he felt a pain at his side. "MERLIN!" He clutched at his side and recoiled in pain.

Merlin was at his side instantly, laying hands on his scar with his eyes glowing gold. He frantically spoke the incantation three times, until Arthur's breathing returned to normal.

Leon spoke, "Are you alright, sire? What just happened?"

Merlin answered, "His wound still has traces of Aithusa's magic. It's powerful to have lasted 1500 years. I'm still working on a solution."

"Is it dangerous?" Leon asked.

Merlin petted Arthur's hair, "I don't know, but it scares me."

Arthur sat up, "Let's not worry about that now. I need someone to tell me how Leon is here? It makes no sense."

Leon and Merlin exchanged a look before Leon spoke to Arthur, "Do you remember when I was found by Druids? I was near dead and they brought me back by having me drink from the Cup of Life."

Arthur's eyes widened and he nodded, urging Leon to continue.

"I survived many impossible battles after that, which I attributed to my skill and good fortune. It was many years later when I realized something had changed in me. After your death, I took a wife and had children. My wife aged, but I did not. My children grew, but I stayed the same. I continued my service as a knight and survived every battle. My fellow knights were killed or retired as their bodies weakened, but mine did not. I remained just as I am. My wife passed, and my children, and grandchildren. When my last granddaughter, Lynette, died, I went in search of Merlin for answers. When he told me that we had both been gifted immortality, I stayed with him and we waited together for your return."

Arthur stayed quiet for a moment, processing. "If you were waiting together for my return, why were you not here?"

Leon glanced nervously at Merlin and Merlin glared back at him. Leon swallowed, "We … had a falling out."

"How long ago?"

Merlin replied with clenched teeth, "1945."

"Why? What happened in 1945?"

Merlin and Leon glanced at each other again. The tension in the air was palpable as Merlin replied, "There's really no need for you to concern yourself with it, Arthur."

Arthur looked at the warlock, "Merlin, you look one second away from strangling him. What happened?"

Merlin stayed quiet, so Arthur turned to Leon. "Leon?"

Leon looked at Merlin who avoided his gaze. "Does he know about the wars?"

For a moment it seemed like Merlin was going to ignore the question, but then he sighed, "No."

Leon nodded and smiled at Arthur, "Perhaps we should all go to the kitchen for a spot of tea, yeah?"

As the three of them walked to the kitchen, Leon stopped in the living room to stare at the wreckage of the couch and coffee table that'd been pushed against the wall, "What the hell happened here?"

Arthur spoke, "Oh, that was me."

Leon looked confused.

Arthur responded with mirth in his voice, "My jigsaw puzzle pissed me off."

Merlin tried and failed to stifle a laugh at Arthur's half-truth and Leon's confused and concerned face.

They made their way into the kitchen. Leon and Arthur sat at the table while Merlin put the kettle on. They looked at each other awkwardly.

Arthur started, "One of you is gonna have to start talking."

Leon sighed, "In the first half of the twentieth century there were two wars. They are called world wars because they impacted every part of the globe. Albion was very involved in these wars and was targeted directly in the second world war in something we call the Blitz. Explosions rained down from the sky and many perished, it was a time of desperation."

Merlin poured the tea from the kettle into three cups. Merlin immediately brought milk and sugar and Leon began to put them in his tea. Arthur noted to himself that Merlin didn't need to ask, he already knew how Leon liked his tea. Of course, he knew how Leon liked his tea. They'd been together for almost 1500 years. Arthur replayed that thought jealously. They had been together for almost 1500 years. What might have happened in 1500 years?

Leon sipped his tea and continued, "But even more unthinkable than the Blitz, in Germany there were horrors beyond imagining. People seen as unfavorable were forced into camps and the most horrible things were done to them. I will spare you these details."

Leon paused and looked down into his cup, as if some monster lurked at the bottom of it. "But then, the impossible happened. There is a thing called the atomic bomb." Leon looked into Arthur's eyes, "The destroyer of worlds."

Arthur's heartbeat raced in fear. He could tell Leon was in earnest and he trembled to think of what that could mean. The destroyer of worlds.

Merlin interrupted his thoughts, "Stop, Leon. You're distressing him. We shouldn't even be talking about this. He just got back, for gods' sakes!"

"Merlin, he needs to know!"

"Why?! Why exactly does he need to know? It was seventy-five years ago."

Leon stood, "Exactly! And if Hiroshima wasn't enough to bring him back seventy-five years ago, what do you think we're walking into now?"

Merlin's eyes flashed gold and his voice rang and echoed with a dark magical quality, "ENOUGH!"

Leon froze and the silence that hung in the air filled Arthur with dread.

Arthur rose and placed a hand on Merlin's shoulder. "Merlin, I need to know. Whatever happened in 1945, I can tell it's important. Please, sit down and let Leon finish.

Merlin's eyes seemed so sad and conflicted, but he relented and sat down next to Arthur.

Arthur motioned for Leon to continue.

Leon sat, sipped his tea, and continued speaking, "The atomic bomb is a thing of science, not magic. It is a force beyond nature, one that shouldn't exist. It can wipe a location entirely off the map. Killing and poisoning its people. A country from across the sea, the United States of America, used the atomic bomb twice to end the war. It was a catastrophe." Leon's eyes were glazed over as he stared far away. "Catastrophe."

They stayed quiet for a while as Arthur processed. He didn't quite understand Leon's words, but he understood the gravity behind them. Something terrible had happened. Something world changing.

He reached out and took Merlin's hand in his. "Now tell me why this means you are no longer friends."

A/N: Sorry for the history lesson, but this is important to Leon and Merlin's backstory. You'll see why in the next chapter.