A/N: Chapter 3 got updated at the same time I posted this one. I fixed some language stuff and edited it to drop honorifics, which I'm doing for now. I haven't seen a non-translated version of the manga (my primary basis for "canon") and it's been long enough since I've seen the anime that I can't put –sans and –chans in the right places for the girls talking to each other. I can handle Keitaroanyone conversations, but the girls talking to each other is my difficulty (old friends generally don't follow the regular rules). I will stick with using last names in place of first names for more formalized relationships (ie, Motoko to Keitaro). I feel that this course of action is preferable to having it done badly, even though I don't love it this way and it looks a little weird sometimes.

The Rebound Effect: Again!
Chapter 4: Escalation

Disclaimer: Characters and setting copyright Ken Akamatsu. Spoilers, those that might appear, would be from the end of the manga series (vol 14). Negima spoilers will be growing slowly. "How magic works" will be at whatever point I've seen to (currently a chapter in the high 50s). Plotline spoilers are currently not existent.

Again, thoughts are represented as /thought/ and spoken text is "text".

"Sempai!"

Keitaro turned as a young feminine voice called out his name. He had been walking slowly back to the Hinatasou through town when the cry, accompanied by the sound of running feet, broke him away from his thoughts. "Oh, Shinobu!' he called back, waving to her and smiling a little as she hurried to catch up with him.

The sun was sinking fully below the horizon and the scattered array of street lamps flared to life one by one all along the street. Motoko's blow had sent him sailing quite a distance, and the walk back had been time-consuming, made more so by his deep thoughts.

"Sempai, we were worried that Motoko might have... overreacted," she said as she caught up with him and tried to slow her breathing. "Everyone is out looking for you. We were afraid you might have been hurt."

Keitaro blinked at the show of concern and offered her a reassuring smile. "No, I'm fine. Aoyama caused me to end up on the other side of town, but I... ah... landed in something soft," he said, trying to cover up his miraculous lack of injury. /I guess this isn't an everyday event for them. Yet, at least,/ part of his mind added darkly.

Shinobu noticed that the sun had disappeared and an expression of worry came across her face. "We need to hurry back. Everyone was supposed to meet back at the base of the stairs at sundown to regroup. I didn't think I was going to find you before it was time to head back. I thought you were probably..." She didn't finish and he could tell that she had been worried about his health.

/You've only known me for half a day, Shinobu, but you are still concerned for my wellbeing,/ he thought as he placed a reassuring hand on her shoulder. "Let's hurry up and get there to meet them, then. I don't want anyone to be troubled about me."

She nodded and smiled at him. The tension in her frame seemed to lessen and he felt relief for that. Upsetting Shinobu had always been one of the more terrible things he had done in his youth and one that he had regretted. As they walked, she fell into step with him, a little behind and on his right side. As they neared the base of the long and winding staircase up to the Hinatasou, he noticed that her nervousness was returning.

"Um... sempai?" she asked as they walked, and he had a feeling that he knew what she was about to ask. "Would it be alright... I mean, could you... Would you tutor me in math?" The last came out in a hurried jumble of words that took him a second or two to decipher.

"Certainly, Shinobu. It would be my honor to assist you," he said with a smile as the expected question came. She beamed back at him and the last of her tension vanished. She rushed ahead as they rounded the corner and spotted Mitsune and Naru waiting at the foot of the stairs. They both seemed a little surprised as Keitaro walked back to them, alive and well.

When Motoko came back from her own searching a short while later with Su in tow, she simply nodded to him, though he was sure she was just a little bit impressed at his resilience.

"The sutra Anurupye Sunyamanyat says: 'If one is in ratio, the other one is zero'. That means that x is going to be zero since y is in ratio with the constants. Then you just solve for y and it turns out to be," he tapped the numbers of the problem with the pencil while doing a simple bit of mental math. "That means y is going to be -4. See?"

Shinobu nodded hesitantly. "Y-yeah, I see... I've never heard of using sutras to solve problems before."

He laughed nervously, trying to remember where he'd learned that particular bit of information and whether or not it was prevalent in the twentieth century. "Yeah, just a little trick I picked up, I guess. But you just have to remember that everything is easy once you've learned how to do it. So just concentrate on each thing as you come to it and when you've mastered it, it will be another tool you can use later to solve harder problems."

Shinobu looked the problem over again and nodded to herself. She yawned widely and glanced at the clock as she did so. "Oh, I didn't realize it was already midnight," she said, more than a little embarrassed. "Thank you for your help, sempai, I did not mean to keep you up."

He offered her a polite smile and stifled a yawn of his own. "No problem, Shinobu. Consider it my thank-you for the cookies you brought."

She blushed and nodded before gathering up her things to head for bed. In the back of his mind, Keitaro idly noted that no one had burst in on them while he tried his hand at tutoring. The first time he had stayed at the Hinatasou, he'd had an escort for a lot of activities, particularly early on. The only one who seemed to hold any opinion about his potential danger to members of the opposite sex was Motoko, and she had been oddly contrite after he had returned from her abrupt flying lesson.

"Good night, sempai," Shinobu offered sweetly as she opened the door and stepped out, almost straight into Naru, who had been reaching to open the door. Naru's quick reflexes saved the tray she was carrying from falling and the two exchanged a quiet word before Shinobu walked past and down the hallway.

Still seated at the table, Keitaro didn't catch what was said, but he called a "good night" after Shinobu as she departed. Naru walked in and placed the tray on the table. Keitaro blinked in surprise at the action. /What's she doing?/ he wondered as he watched her turn to close the door. He noticed the three cups on the tray and surmised that she had intended to bring tea to the study party.

She took a seat opposite to him at the table and placed her hands flat on its surface. She leaned forward, looked him squarely in the eye, and said in a very flat tone, "I know."

His mind raced as he tried to decide what it was, exactly, that she knew. Had she discovered evidence of his magical work earlier in the day? Did she know about his journey from the future? Was some foreign psyche embedded in her young body? His thoughts swirled and he finally reined them in enough to respond weakly. "You know?"

"Yes. I know that you're not a Toudai student," she answered in a very forceful voice, but he felt some relief at the declaration.

"Oh, yeah, that." He laughed lamely, trying to cover relief as he sought to dredge up old memories. "How did you... oh, yeah, that's right. We attend the same preparatory school, don't we? You're the girl that's top in the nation on the mock tests, aren't you?"

It was her turn to blink in surprise at his ability to recognize her out of her study outfit. "Yeah. That's me."

He nodded in satisfaction that he'd partially diffused whatever head of anger she might have been working up. "It's kind of funny... I was a little groggy after passing out and, for a while there, I forgot I hadn't gotten into Toudai yet. There hasn't been, you know, a good time to set it straight yet. What with Aoyama trying to kill me and all."

She poured the tea, though he could not be sure whether it was because she was thirsty or because she wanted a second to think. "Do you think they will let you stay when they discover the truth?"

He detected a stronger than necessary emphasis on the word 'they' when she said it, and he began to feel that she was the first person he would have to make amends to. "I... I can only hope that an understanding can be reached. I never meant to deceive anyone. It's just that I really need a place to stay. This year, I am certain to get into Toudai." The certainty in his voice was so strong that she nodded along as he said it. /Of course I can get into Toudai... it should be simple enough at this point,/ he mused.

"You seem determined to do so," she said, looking into her own tea, "and Shinobu seemed happy that you were helping her out. I think you might be able to convince them to let you stay."

He nodded, wondering again who, exactly, she was referring to. For a long minute, he watched her across his own cup of tea, studying her and comparing her to the glowing memory of his first wife. This Naru was very young in comparison to his memory, but the same beauty was there. She certainly had the same personality.

"I... thank you for being so quiet about this. I really am sorry," he said, bowing his head slightly in shame. /I really didn't mean for it all to happen the same way it did the first time./

The moment was broken as Mitsune slid the door to the room open and cleared her throat noisily. "My, what a homey scene," she said coyly. "I didn't know you were interested in him as well." She laughed lightly as Naru rose and glared at her. "Keitaro, you might not realize it, but having tea alone with a man in his room is pretty close to a proposal from our little Naru."

"Kitsune," Naru growled.

"Oh, I'm just teasing. Calm down," she said with another laugh and a teasing smile.

"Umm... Mitsune, do you want to join us or something?" Keitaro offered in a vain attempt to calm down the situation again.

"Oh, no, I just stopped in to tell you that you've got a visitor, Mr. Toudai. She's down in the living room. You've got weird friends," she said as she ducked out of the opening and down the hall to avoid the glares Naru was sending her way.

Naru tagged along behind Keitaro as he made his way down the stairs to the living area. /Who gets visitors at this time of night?/ she wondered. /And what's he doing having visitors at a time like this? He should be worrying about getting kicked out for lying to us./

She kept her concerns to herself as she came down the stairs behind him. The person waiting in the living area was about as far from what she could have expected as possible. A large heavy-looking trunk had been rolled into the room, and a small backpack rested on top of it. The visitor herself was a small girl, not even as old as Shinobu, seated on the couch.

The girl saw Keitaro and babbled something in what sounded like Cantonese as she got up and advanced on him. He responded in the same language and raised his hands defensively. The girl lunged forward, but instead of attacking him, she hugged him.

"Umm... Keitaro?" Naru asked, not quite sure what to make of this.

"Oh, ah..." Keitaro said, trying to pull the girl off of him long enough to introduce her. Finally, she released him enough that he could talk though he was blushing furiously. "This is Kagurazaka Asuna, she is... umm..."

"I'm his wife," the girl said with a hard smile and bowed. Keitaro looked at her, shocked as she said it, and the girl mumbled something in Chinese to him as she did so. The look on her face made Naru almost as interested in what they were saying in the other language as she was in why, exactly, Keitaro was married to a preteen.

A/N: Well, raise your hand if you saw that one coming? Didn't think so. Asuna is, fairly obviously, from Negima. I've never actually seen a Love Hina/Negima crossover that used main characters, so this will be fun (I've seen several with the thousand master involved, but the timeline makes things hard... as we're about to see).

Using the magna timeline. In the manga, Keitaro gets beaten up less violently in the start than in the anime. Whereas the anime sends Keitaro flying quite a lot, he doesn't actually go across town for quite a few chapters in the manga. Thus, the fact that Motoko sent him flying that far and he lived is a bigger deal than the anime might suggest. The other girls were also significantly less angry with him than they were in either anime or manga, which lead to them being more concerned.

The math trick. Yes, there is a real mathematical sutra thing. It's called Vedic Math (plug it into google if you want some specific info). Basically, it's a set of sutras which help you do some simple (and not so simple) stuff with mathematics. Personally, it doesn't look like it'd be too much help for most people, but Keitaro's from a future that is both more India-centric and mathematics oriented than our present so it's quite likely that he would know and use such tricks. If only because it would help him fit in. Right now, it's being pushed as a way to shave 10% of your time off of an engineering school entry exam. I imagine that Toudai test takers might go for it, as well.

Comments and criticism much appreciated. A huge heap of thanks goes out to those brave (or is it foolish?) souls who preread this for me.