Disclaimer: I don't own Sherlock or Arsène Lupin. Nor Ellery Queen.

My third Sherlock Holmes/Arsène Lupin crossover, and none of them are in the same universe. Funny how that works out. This is however in the same universe as Felons, Skulls, and Gratuitous French, which details in all its glory the crackslash OTP of Arsène Lupin and Ellery Queen. Basically the idea of this 'verse is that all the classic detectives exist in the modern AU that is Sherlock, and that Arsène/Ellery is OTP, but Arsène doesn't have problems badgering his exes. Yay!

When John Watson, Retired Military Doctor, first met Arsène Lupin, Gentleman Burglar, Sherlock Holmes, High-Functioning Sociopath, was fuming.

John still wasn't quite sure if that was the right word.

The fuming wasn't quite all Arsène's fault, but he definitely helped. Sherlock had in fact been fuming the entire way home, which had been dragging on John's nerves all the way home, and by the time they reached Baker Street John wanted nothing more than to shut himself in his room and ignore the existence of his flatmate entirely.

John still wasn't quite sure what Sherlock was fuming about.

Whatever it was, the problem at hand was instantly forgotten, at least by John and likely by Sherlock if his reaction was anything to go by, though with Sherlock you never really knew, the second they entered their flat to find Arsène lounging on the couch.

"You," Sherlock growled. John liked to think that he was getting good at discerning how Sherlock greeted people, and if he was correct then this was someone with whom Sherlock had locked heads with in the past and who was smart enough that Sherlock didn't feel the need to belittle their intelligence every so often. In short, the Arch-Nemesis class of acquaintances.

"I let myself in, I hope you don't mind," Arsène replied with a wave.

"Wait, you have a key?"

Both other occupants glared at John. "Don't be stupid," Sherlock scoffed, as he did every day, though this time the scoff was colored by the fuming of before and the ire of finding this person on his couch. He then quickly turned back to Arsène. "You promised you'd stay out of the country!"

"I didn't promise, I implied," Arsène specified. "Also, I lied." A silent, 'Well duuhhh,' was worded with waving hands.

"What are you doing here?" Sherlock demanded, getting straight to the point.

Arsène managed to look affronted. "What, I need a reason to break into your flat and lounge on your couch?"

"What. Are. You. Doing. Here? And get off my couch!"

Arsène rolled up gracefully with a slight bounce. "If you must know, I got bored. I came over to see if you wanted to play, because for some reason you've been avoiding Paris like the plague." He added a small pout. "Did I not live up to your expectations last time?"

John still wasn't quite sure what the look on Sherlock's face at the time was.

An arm swung around towards the door. "If you're bored, why don't you just run along to New York and play there?"

Arsène made a show of dawning comprehension. "Oh, I get it now! You heard about my little fling with that American author and now you're jealous! So cute! Start begging and I might just take you back!"

"You're acting like you broke up with me!"

"No, it was you who broke up with me."

"It couldn't have gone either way because we were never dating!"

"No we weren't, were we Sherlock? We just really liked sticking each other in handcuffs."

John still wasn't quite sure what was going on at all, even though he did know that he was enjoying bearing witness to it.

"I ought to call the police right now," Sherlock threatened.

Arsène scoffed. "Like that'll scare me off. Instead, why don't you introduce me to your new monkey?"

"Yes," Sherlock mumbled distractedly as he wandered over towards the mantelpiece. "John, Arsène, Arsène, John."

They shook hands. "Nice to meet you," Arsène said, flashing a winning smile.

"Monkey?" John questioned.

"There was a slight incident involving the first one in Jordan."

That... explained absolutely nothing at all.

John made an 'ah'-ing motion regardless. Sherlock picked up the skull on the mantelpiece and glanced it over. "Arsène, what have you done with my skull?"

"It's been mailed to New York. You detective types are all alike, you know that? I took my author friend's skull before I left and figured I should recompense him in some way. You can't keep that by the way, it's a memento."

"You mean before you were run out of town?"

Arsène made a shooing motion with his hand. "Details, details."

"Wait, run out of town?" John repeated, not quite following.

"Simple. Arsène here would only think of recompensing someone if it was serious, therefore he would only leave if there was a bad breakup or he was run out of town. And his author friend is rather well-connected with the New York police, so since there was no blowup about the NYPD asking for his head, I must assume the common man ran him out. Also, I've read the editorial pages of a number of New York newspapers with information pertaining to the topic."

"Except you can't arrest someone because there was a bad breakup with someone you're friends with, the police don't work that way," John pointed out, confused.

"They can if the subject's father is a police inspector and the subject's ex is wanted by Interpol, among others."

John looked at their unexpected, uninvited houseguest in a whole new light. "...The hell?"

"Indeed," Sherlock said dully.

"And why aren't we calling Lestrade?"

"Because that would be boring and expectable. Also, it wouldn't do a damn thing." Sherlock glared once again at Arsène. "Now get the hell out."

"Let me think about it... no."

"Breaking and entering..." Sherlock warned.

"Out of what, a thousand?"

"I could take you down."

"I'd like to see you try."

John still wasn't quite sure whether this was actual hatred or unresolved sexual tension.

Whatever it was, it seemed that Sherlock had had enough of it as he suddenly lunged at Arsène. Arsène neatly side-stepped, but Sherlock seemed to have been expecting that and changed course at the last second. This time Arsène tried throwing Sherlock with his own momentum, but Sherlock hung on and they both crashed to the floor.

John quickly turned to look for a phone with which to call Lestrade and the video camera with which to get this on tape. But before he find either something was shoved under his nose and he smelled something distinctly un-fresh air...

When John came to, the first thing he noticed was the cold metal band around one of his wrists. He supposed this said something about him, but that wasn't foremost on his mind at the moment. What was foremost was the discovery of Sherlock on the other end of the handcuffs and a leg of the coffee table between them. "Sherlock?" he asked, noticing that the other's eyes were still closed.

The blinds were shut but someone was home. "I really hate him sometimes."

"Oh, only sometimes?" John asked, his voice going slightly higher as it tended to do when he was disbelieving.

"I believe the term is 'frenemy'."

John snorted. "I think the term you're actually looking for is 'foe yay'."

"What?"

"It's when two people who hate each other flirt horribly whilst battling to the death."

"Boring. That is interesting," Sherlock nodded towards the door. That was when John noticed the piece of paper taped there with large words written on it – big enough, at least, for the two of them to read it from their position on the floor. In two days time I'll ransack the Hickman Gallery. See you there!

"Did he really just leave that there for the world to see?" John asked.

"Wonderful, The game, John, is on!"

Don't ask about the monkey incident. I just know that I got to that part and really wanted Arsène to refer to John as Sherlock's new monkey, I don't. know. why. Felons, Skulls, and Gratuitous French can, if you're interested, be found on my profile page as per the usual, as well as the other two Sherlock Holmes/Arsène Lupin fics. Gratuitous pimping of fics! Reviews are adored and responded to!