For this, like for so many other things, you may blame the Togakushishrine LJ community. In between bouts of multi-verse conquering, they had a crack-pairing challenge. This was the result, an evil crossover pairing resulting from comparing the characters' offspring and finding that a lot of their traits could conceivably be genetic. Woe is them (not that it wasn't already).

Disclaimer: The joint property of AlMiles, CLAMP, and whoever else owns them today.

Canon: You can't prove anything.

Warnings: Umm, het? And, y'know, the evilness of an X/Smallville precanon crossover in general. And the Devil/Magnificent Bastard. And homicide, but that's really no surprise, is it?

Predators

Setsuka didn't usually hold with taking unplanned kills, but when the man sauntered through the park and stood directly beneath the Tree, how could she resist? Anyway, she reasoned with herself, he looked like a significant person—rich black suit, the best that money could buy, absurdly confident attitude—and if the expression on his face was any judge, he would be a challenge. Setsuka always adored a challenge.

He was more of a challenge than she thought, she realized when he, without reacting at all, spun casually around and grabbed her by the wrist before she could get close enough. Against her will, Setsuka was impressed. He hadn't seemed to see her until it was too late for her to react. Yes, indeed, he was very challenging. And, she noticed, rather attractive too, in a dangerous kind of way,

"Well, now," he smiled into her impassive face, "what were you planning on doing?"

"Killing you," she replied. This was not a man it would be worthwhile lying to.

He seemed more amused than otherwise. "Really, now? I'm afraid that isn't as easy as the last several people thought. If you don't mind my asking, how much were you paid? If it was less than ten thousand American, you were cheated. I believe the going rate is…somewhere in the fifteen thousand range, and climbing."

"I wasn't paid," Setsuka said, annoyed by the comparison. She was not some hired thug you could buy to cosh somebody in an alley! Then intrigue caught up with her, and she asked, "Do people try to kill you often?"

"About once a week," he said. "Less, of course, since I came to Japan. It's been quite a vacation."

Setsuka thought she could permit herself a smile. "Do forgive me, in that case, for interrupting. I assure you, I hadn't been intending to."

"But do you intend to now?"

She had to think before responding. It was odd, but while part of her wanted to finish her challenge the way she had begun it, another, louder part told her not to. Versatility, after all, was very important, and there were much better ways to spend a day than trying to get bloodstains out of her clothes. So she smiled and said, "Would you release my hand if I said no?"

"Quite possibly."

"Then no, I do not."

The man relinquished her hand with a laugh. His eyes never moved off her even when he was laughing, Setsuka noticed. That was a rare skill. "In that case, would an impolite conversation be too much to ask?"

Setsuka raised her eyebrows. Was he a foreigner? His Japanese was unaccented. "Surely you mean 'polite'?"

"No, not really. It is refreshing to find someone who is willing to admit to planning to kill me. One does, occasionally, tire of diplomatic evasions."

"In that case, certainly." Setsuka smiled. This man was far more entertaining than her usual quarry. "Shall we sit down?"

They were comfortably seated on a bench—the man, she noted, was one of the few individuals who could seem both comfortable and dignified on a backless bench—before he asked, "By the by, what precisely were you intending to do to me? I admit that there are some quite critical nerves on the back of the neck, but a bare hand is not generally considered the most effective of weapons."

Setsuka smiled. She doubted he, perceptive as he was, could read her smile. "It's a family secret."

"I see. Family secrets can be convenient things to have, can't they?"

"On occasion."

"Speaking of which, I seem to have been remiss in my manners. It is, I gather, the height of bad manners to converse with people to whom one has not been introduced, and you Japanese are very attached to manners." Setsuka filed the information away in her mind. So he was a foreigner, then, and rich, to judge from his clothing. She made a mental note to reread the recent papers for any mentions. It was always good to know your prey. "Lionel Luthor, at your service."

"Setsuka Sakurazuka. It's an honor, I'm sure."

The formalities taken care of, they returned to their conversation on the subject of appropriate weaponry. It was, perhaps, not the most orthodox of topics, but Setsuka was not an orthodox woman, and she was quite certain that Mr. Luthor was not an orthodox man. He was certainly knowledgeable enough on the subject to make the discussion both interesting and educational, and Setsuka was therefore put out when he looked at his watch and said, "I'm terribly sorry to break off this most absorbing chat, but I unfortunately have a business meeting to attend. In exchange for abandoning such a lovely lady, might I have the honor of escorting her to dinner this evening?"

Setsuka smiled. "By all means, Mr. Luthor."

"Call me Lionel, please. Would seven o'clock suit?"

"Perfectly. I'll meet you here."

"Until tonight, then."

The restaurant he brought her to was Italian, the sort of elegant place she had grown used to visiting alone. The light was low, but not so low that she didn't notice him dropping a small amount of white powder into her wine. She handed it back to the waiter with a wink, and was unsurprised when his glass received the same treatment after she had taken the opportunity of Lionel's ordering to add a few drops of a certain colorless liquid. Setsuka was quite sure of the game they were playing; she had played it often enough before, although never with such an expert opponent. Every move she made was returned deftly, keeping her on her mettle as her equally adroit responses kept him on his. By the end of the evening, Setsuka was sufficiently elated by the discovery of an opponent worthy of her steel that she felt no qualms about suggested a further meeting the next day. Presumably Lionel felt much the same, for he agreed.

Day followed day, and one thing led to another, which other sooner or later led to Lionel's apartment and the first of many extremely pleasurable evenings. Thereafter, it was tacitly agreed that any minor attempts at murder should be left at the bedroom door. There was a time and a place for such things, and while you were already quite focused on something else was neither then nor there.

Quite unfortunately, from Setsuka's point of view, Lionel had to return to America after a month to continue the building of his company. They parted without either tears or, surprisingly for them, homicide. Of course, Setsuka killed five people on her way home from the airport, and no one ever knew what happened to Lionel's next business rival, who was foolish enough to greet the plane in Metropolis, but that was as much a way of life as anything.

They did, of course, keep in touch, by letter, telephone, and occasional visit. Both, of course, scrupulously burned the letters after committing them to memory. And, if it came to that, Lex never did find, in his more or less unrelated searches of the mansion, the scrupulously sharpened katana with 'LS' wrapped around the hilt which Lionel had received the Christmas Julian had been born. Neither did Seishirou, going through his mother's effects, discover a finely made and still-loaded gun bearing the same insignia. After all, Lionel and Setsuka were very good at hiding things, from bodies to birth certificates.

It had been worth a week's sabbatical in Japan some months later, certainly, for Lionel to meet his eldest son in person. The infant was clearly Lionel's son at three days old, from shock of dark hair to already-focused eyes. He looked straight at everything, as if filing it away for future reference. Setsuka was unabashedly proud of him, if still slightly annoyed at having been unable to kill anyone for six months. Morning sickness, apparently, could do what no amount of gore could not. She had already decided to name him Seishirou, after her grandfather. Lionel, smiling in his usual predatory way, said that even though Japanese did not usually give middle names, he would like to, and Setsuka agreed. So he was named Seishirou Leander, according to his birth certificate and no other document, ever.

The two adults spent a pleasant week visiting favorite places and discussing who would raise Seishirou. There was no question of marriage; Setsuka was as adamant to remain in Japan as Lionel was to remain in America. Instead, they agreed that the occasional vacation spent overseas on Lionel's part and regular letters and pictures on Setsuka's would suffice. She refused to accept money. Lionel was growing wealthier every day, but she had never been poor, and it would have been too inconvenient, besides putting her in a position she had always avoided, that of being in someone's debt. Lionel laughed and didn't insist. He could be quite sure Setsuka would raise their son to be as skillful a predator as he would.

And she did. But that is another story.

The More-than-Slightly Worrisome End

Names and such are ordered American-style, because 'Setsuka Sakurazuka' sounds marginally less silly than 'Luthor Lionel'. Yes, I did get tired after one conversation. There's only so much verbal dueling I can write at one sitting.

No one in this fandom but me knows half of what I wrote down, which makes me obscurely depressed. Still, depression is boring, so I won't bother. But reviews are appreciated.

Any egregious errors in characterization are errors of ignorance, not intent. Whether this makes them better or worse is your call.