Of all the ways Saguru expected to spend his first afternoon back in Japan, sitting on a mat in Kuroba Kaito's bedroom while his number one KID suspect carefully smeared a dozen different creams onto his arm to 'test' potential cures would never have occurred to him.

It left him feeling... conflicted.

Because on the one hand...with nothing to do but sit there, Saguru was quite free to look around his bedroom and take advantage of this excellent opportunity to snoop for concrete evidence that Kuroba was indeed KID.

But on the other hand, Kuroba was going out of his way to help him with no obvious ulterior motive that he could see-Saguru frowned, running his eyes over the room again. Wait a minute. Why wasn't-

"Would you quit fidgeting?"

Saguru jerked his eyes back to Kuroba who was glowering at him, a gel like substance in his hands, hovering half a centimeter over his arm. He ducked his head slightly, again feeling his cheeks heat up. "Apologies, Kuroba-kun. My mind wandered from the task at hand."

Kuroba raised an eyebrow. "Wandered? To what?"

Like it would be a good idea to explain that he'd been looking for evidence of a connection between Kuroba and KID. He shrugged a shoulder. "It's nothing."

Kuroba rolled his eyes, placing the gel above the six lines of cream already on Saguru's arm. "You might as well tell me what you're thinking, Hakuba. I can see it eating at you."

Saguru shook his head, fully regretting looking over the room in the first place. "It would not be polite, Kuroba-kun. Since you are helping me."

Kuroba scoffed, though his eyes danced with silent laughter as he applied yet more gel from a different bottle. "Not polite-so you've noticed something….KID related in my room and you're what? Trying to not investigate?"

"Correct."

He smirked, pulling a towel out of nowhere, though Saguru suspected it had been hiding in his sleeve, to wipe at the first of the creams revealing the skin underneath it unchanged. "I said I had nothing to hide. Tell me. You're not going anywhere any time soon."

That was true. Saguru exhaled, watching as Kaito wiped away another line of cream to reveal his skin unchanged. "For being KID's number one fan…" He said slowly, picking his words carefully. "I find it….odd. That you have no KID merch whatsoever here in your bedroom."

Kuroba paused, eyes darting about the room before he smirked. "Observant."

Well, he had asked. "I am a Detective, Kuroba-kun."

"Mmmm. And I suppose you have a ton of detecting stuff in your room?"

Kuroba would know. Though Saguru had no physical proof his classmate had ever entered his house. "Yes. I do in fact. But you have said multiple times you are a magician and the only…" Saguru tried to not grimace. "The only KID or non KID related magician thing I can see right now…" He tilted his head towards the wall. "Is that portrait you have there. It's...odd. And I'm-" He exhaled, staring down at his arm and still blue skin. "I'm trying to not question it because that would be...rude since I am a guest here, to try and…" He shook his head. "You are helping me, Kuroba-kun. I'm not-" His mouth twisted. "I don't want to-I just can't help it."

"A detective sees a mystery and needs to solve it." Kuroba said softly. "I'm familiar enough with the concept, you've prattled about it in class often enough."

Saguru raised an eyebrow. "I wasn't aware that you were listening." Of course, he figured Kuroba had been. Even if his eyes would glaze over whenever a case not involving KID was brought up, Kuroba had proven time and again that he knew more than he appeared to. "After all, not all my cases involve your precious Kid-sama."

Kuroba snorted, slightly shaking his head. "Precious, huh?" He said under his breath as he pushed up his long sleeves to the elbow before grabbing another bottle of gel.

That tone. Despite himself, Saguru leaned forward, careful to not disturb the tinctures Kuroba had smeared on his arm. "Is he not?"

Kuroba was much slower at wiping away the third cream, again revealing Saguru's skin unchanged. "Did you know?" He asked, carefully applying more gel to the spot. "That I was just like you-well not exactly like you." Kuroba looked up, smirking. "You're too boring Hakuba, but I didn't like KID when he first reappeared either."

Huh? Saguru blinked, raising his eyebrows. "You...but-in class!" From his very first day in school with the magician, Kuroba had spoken nothing but KID's praises. To hear that he hadn't liked KID when he was KID-that-how was that possible?

Kuroba chuckled, though his eyes held no laughter now. "Honestly, I had no idea the guy existed until Aoko told me about him the day after his first heist...I was offended by KID actually."

"You were?" In all his research-Saguru had never known this fact. Aoko hadn't brought it up at all when he'd questioned her about her childhood friend.

Kuroba nodded. "Of course. How could anyone consider a thief." His eyes flashed at the word. "To be the best magician in the world, especially after all Aoko knew about my Father?"

Father. Kuroba Toichi. A famous magician who had died nine years earlier, leaving his wife and son behind.

Kuroba shook his head, wiping at the other creams on Saguru's arm one at a time, checking to see if they'd altered his skin. "I told her that day I would prove KID was nothing but a two-bit wacko con man. That I was the better magician and catching him would be a walk in the park." His mouth twisted. "She was rather bitter when I came back after that second heist proclaiming myself as his number one fan and that I no longer wanted to catch him."

"It does seem...a rather odd change of heart." Saguru said slowly, staring down at his blue arm. If what Kuroba said was actually true. He'd have to confirm with Aoko at a later date. But if it was true. And that Kuroba wasn't just acting for Aoko's sake...then that first heist had been-That Kuroba had met-

A third phantom.

One who'd somehow been convinced to stop holding heists after Kuroba went to confront them.

Sure, Saguru had noted a couple of inconsistencies in those first two heists compared to the latter ones. Like the wearing of a wooden mask over his face when confronted by the police. But the thought had never crossed his mind that Kuroba hadn't been the one to instigate KID's return. That another had been involved.

He looked up, watching Kuroba as the magician worked. What exactly had happened at KID's second heist? "Did you even go see KID that night?"

Kuroba raised an eyebrow. "Of course I went. I told Aoko I would catch him didn't I?"

"Did you?"

His classmate grinned, smearing lotion on his skin. "If Nakamori-keibu can't catch him, and you can't catch him, what makes you think that me, a simple magician, could?"

"Because a simple magician, as you say, doesn't think in the same way as us detectives do."

Kuroba had proven that time and time again. After all, KID had stayed one step ahead of the police for nearly every heist. Always managing to escape. To wiggle his way through and out of every trap set for him.

"A good thing too. Your lives are so boring compared to mine."

"Boring." Saguru repeated with a soft scoff. "Are you serious-"

"Never." He winked.

Saguru rolled his eyes. "Liar." He'd seen Kuroba be serious. In the moments when his classmate thought no one was watching.

"Magician actually. Not the same thing."

He exhaled. At this point it would probably be best to drop the argument. "So…" Because now Kuroba had him intrigued and like his classmate said, he couldn't leave a mystery unsolved. "What happened that night, Kuroba-kun? What made you change your mind about KID?"

Kuroba shrugged a shoulder, a careful wariness shining in his eyes. "What makes you decide that one suspect is the culprit when you originally thought it was another?"
That was easy. "New information came to light." His breath caught. "New information came to light." He repeated softly.

Kuroba gave the faintest of smiles. "Bingo."

But if new information came to light...and that resulted in Kuroba taking over as KID instead of capturing him, because Saguru was certain that his classmate was the phantom thief now even if he hadn't been in the beginning-He frowned, resting a hand on Kuroba's arm to stop him from adding more creams that obviously weren't working as he met the magician's eyes.

"What did you learn?" He asked, keeping his voice low. And why was Kuroba choosing to reveal all this to him now?

For the first time, he saw doubt enter the magician's eyes. A slight twitch from the corner of his mouth, his shoulders lifting a fraction of an inch in defense. Kuroba ducked his head, staring at Saguru's hand on his arm, staying silent.

Saguru narrowed his eyes. Kuroba had brought him here for a reason. Didn't do anything without cause. He too looked down to his blue hand, resting on Kuroba's bare arm since he'd pushed up the sleev-wait.

There. A tinge of blue barely visible at the crook of Kuroba's elbow.

"Pardon me." He whispered, leaning forward to push the sleeve up further, revealing a partial blue handprint on the magician's arm before Kuroba could move.

A hand print that-He placed his own hand along the mark, ignoring how Kuroba tensed. Saguru's breath caught in his throat as his fingers lined up perfectly.

A match.

The odds of Kuroba having a blue handprint on his arm the same shade as Saguru's skin in the exact same spot where he had grabbed onto the officer when getting out of the vat was-

Impossible.

Which meant Kuroba had been in London, disguised as a police officer, while Saguru was there. Why? How?! KID hadn't announced a heist and no one had indicated that Kuroba had also been gone at any point in school today. Why then did-? He looked up, biting back the questions on the tip of his tongue.

Saguru would have never seen this if Kuroba hadn't pushed up his sleeves in the first place. He could have easily kept the mark hidden by keeping his sleeves down, meaning that revealing this mark….was intentional.

A test.

To see how he would react?

React to the possibility that Kuroba had been there...as KID? Even if there had been no heists announced while they were both in London?

Saguru licked his lips, slowly pulling his hand back as he looked up into Kuroba's face. A face that once again had the blank mask pulled on, revealing nothing of what his classmate was thinking.

The handprint on his arm was only a partial. The edges jagged. An inconsistency with how Saguru had held onto the officer's arm in London. But made perfect sense if it meant that Kuroba had already figured out a cure. Had one ready to use.

Which also meant that there had been no need to test the creams and gels on Saguru's arm if Kuroba already had the answer to getting rid of the dye. Which meant there was no reason for the blue handprint to be there unless Kuroba had purposely left it for Saguru to find. Which meant that Kuroba could have, for all intents and purposes, cured him at school along with his classmates and had chosen not to. Had chosen to bring Saguru here. To his house. Into this room.

Why?

Saguru slowly exhaled. "I suppose." He said, searching for the right words to use, to not launch into questioning his classmate then and there. "I owe…someone." Because he didn't know just who Kuroba had been. Himself or KID? "My thanks. For saving my life in London?"

Kuroba's tilted his head a fraction of an inch in acknowledgement, the tension in his arm under Saguru's hand vanishing, leaving him with the impression that he had managed to pass at least part of this odd test his KID suspect was putting him through.

"And as part of this...thanks." Saguru rested his hands in his lap, studying Kuroba's body language for any hint of what was wanted of him. "Am I being asked to...not solve this mystery you're dangling before me about KID and your actions that night of the second heist? Or to solve it?" Because he really wanted to know just why Kuroba had chosen to be KID especially if he wasn't the one to trigger the phantom thief's reappearance.

Kuroba moved, taking Saguru's arm and carefully wiping down his arm. "You're being asked…" He said softly, looking up to meet his eyes. "In exchange for removing your blueberry color." He pulled the towel back, revealing a single stripe of normal colored skin on Saguru's blue arm. "For your assistance in the near future."

Saguru's heart skipped a beat, his mouth going dry as he ran his fingers over the patch, establishing that it wasn't a trick and that the dye had actually left his skin. "My help? I'm guessing not as a detective. An accomplice?"

Kuroba huffed a laugh, shaking his head. "So quick to assume you're being asked to break the law."

"Isn't that what-" Saguru cut off, pinching the bridge of his nose, closing his eyes. He didn't know if this favor was for KID or for Kuroba. Even if he thought both were the same person he hadn't yet seen Kuroba break the law. Which meant this favor could be relatively harmless.

Or it could be breaking the law.

But if it meant not being blue...would he be okay with doing that? "What is being asked of me then?" He asked, noting that Kuroba hadn't indicated just who was doing the asking.

"Something happened that second heist." Kuroba said softly. "Something that meant I changed my tune. Came to support KID instead of chasing him."

Something that made Kuroba become the thief instead of catching him. "You want me to stop chasing KID?"

Kuroba shook his head. "You will be expected to act normally in all aspects of your life, Hakubaka. That is the key. For no one to suspect you."

Saguru looked up. "To act normally." He repeated, a bad taste in his mouth. So what? KID could use his face in a heist? "That hardly seems like a favor."

Kuroba exhaled, running a hand through his hair before pushing his sleeve back down as he glanced to the painting on the wall, the corners of his eyes creasing. "In a future moment...you will be asked to not return something given to you at a heist. If this occurs….and…" He took a breath meeting Saguru's eyes. "And I…"

Saguru's eyes grew wide. Was Kuroba-

"Do not show up to class within the week afterwards. You will need to leave." Kuroba kept eye contact. "Take it and go somewhere that no one would suspect you to go. For this item once found...it cannot be returned and those who seek it...will be furious to not have it. They will not be afraid to kill those who get in their way."

Kill those who seek it? So Kuroba-KID was trying to find something before someone else did? Was that why he kept returning all the other jewels? It wasn't the one that these...murderers were wanting? Saguru drew in a careful breath, heart pounding in his ears as he stared at Kuroba. "If you do not return-"

"Leave it to Nakamori to find me." He said simply. "Your priority will be protecting what is given to you." Kuroba gestured, a shampoo bottle appearing in his hand. "For it cannot, under any circumstance, land in the wrong hands. If you are able to. Destroy it. It brings nothing but evil."

He sounded so certain. "How do you know?"

Kuroba shook his head, eyes darting to the painting and back. "Do we have an understanding, Hakuba? Your assistance to stop a darker...entity...in exchange for this?" He held the bottle out to him.

Saguru bit the bottom of his lip, staring at Kuroba. He didn't like it. Didn't like it at all. But this...this hinted at something bigger going on. A dark plot in the underground that Kuroba-KID was attempting to prevent. "Why me?"

"Because you've proven you can be trusted." He said simply.

Trusted. Saguru exhaled, shaking his head. "I don't like this. But if it helps." He took the bottle. "Just promise me this, Kuroba-kun. That you'll come back alive."

Kuroba winked. "Go take that shower, Hakuba," He said instead, a hint of KID's smirk playing on his face. "I don't think KID would like it if his Tantei-san remained blue forever."