As Shinichi woke up this specific morning, saw the sunrays puddling down on his wooden bedroom floor, smelled the scent of coffee hanging in the air around him, heard the birds chirping outside...
He still noticed something was wrong. His bed was empty.
"Kaito?" he muttered worried and rubbed his eyes still half asleep. The thief never rose before him, to have the bed empty at- a short gaze onto the clock- 6am was beyond concerning.

Shinichi slipped out of the way too comfortable sheets with more or less amount of necessary willpower and yawned. Early. Too early to deal with this.
"Coffee," he mumbled, nodding to himself.
First coffee.
Shinichi shambled into his kitchen and felt with his hand for the coffee pads... much to his surprise, he found a small note on top of the box.
First coffee. Then the note.
A good minute later he had a full mug inside his hands and as two sips followed, Shinichi felt his own braincells to reboot.
"Kaito?!" he gasped, turning pale. Finally he had realized what was actually going on. His eyes flew over to the note and Shinichi narrowed his eyebrows, examining it.

If you found this note first, congratulations you sleepyhead, you missed the note on the bed. Go read it. And yes, I do know you prefer coffee over a case of my disappearance.

Shinichi stared at the note for a few seconds before he groaned out and stomped upstairs again, heading for the bedroom. And really- arrogantly sprawled out on Kaito's pillow- a note. With a heart?
Shinichi picked it up and stifled a grin.

Once the clock strikes seven
Your reward will crumble
Dark shall destroy it
But so will the light
Hurry Meitantei
Back to the day everything begun

Shinichi rolled his eyes with a grin and shruddered with exitement, god, how he loved riddles and Kaito just gave him the best way to spend Easter.
Where was this going to lead him?
"Back to the day everything begun... Ha. Easy. Our first meeting. The clock tower."
The detective dressed and kept a cautious glare onto the clock. Once he finally got ready, it was almost a half past six. He had to hurry.
Arriving at the clock tower, he rechecked the note. Dark and light were both harmful? And why exactly seven in the morning? Shinichi tried to think but the sun tormenting his eyes distracted him.
"The sun!" he exclaimed, realization hit him like a train. His goal was on top of the clock tower, and at 7am the sun would shine into a specific corner... Shinichi smiled as he took the elevator. In that specific corner the thief had hidden himself on their first meeting.

His guess had been right, a black box throned on the memorial place with a magnifying glass set up above. Shinichi calculated that once it was seven in the morning, the sun would have hit the magnifying glass and both the black box and the light would have destroyed whatever was inside.
Curiously, he opened it.
"C-chocolate?" he gasped and blushed. A chocolate heart rested inside, obviously selfmade and a new riddle was engraved into it.

You made it, congratulations!
But your task is far from over.
You asked me
"What will you do, KID?"
And I replied
"I will stay in the middle."
Do you remember? Behold my favorite critic, the answer to my riddle carries the colour of my former target.

Shinichi made a full stop on his way out and his eyebrows narrowed. He had asked that countless times yet KID had never given this answer. Only...
"Ah! His teleportation trick!" Shinichi exclaimed and startled the security guard next to him, who watched him bounce off with a strange look on his face.
"Ginza Plaza..." the Beikan kept repeating under his breath, "Ginza Plaza... the target had been the purple nails. I had his trick figured out and thought I had him, but..."
I will stay in the middle.
Shinichi smiled. He had been so baffled by this, he hadn't seen his escape coming at all.

He hadn't even observed the whole Ginza Plaza and yet a small shop caught his eye. Rather, the cashier.
"...purple jacket..."
He changed his direction and went right into the shop, a little confused as why KID had chosen a florist.
"Uh... Hello. Could you tell me if a man who looks similar to me has entered your shop?"
The cashier looked up and a wide smile came onto her lips. How ironic, now Shinichi noticed the colour on her nails, too. Purple.
"So you are the one to receive the order? Wonderful. Wait here, please."
She turned around and headed into the employee area, only to return a few seconds later with a huge bouquet of white and red roses.
"Lucky you~ Your boyfriend swooned over you the whole time he was here."
Shinichi jawdropped yet took the flowers. Huge. Flashy. Pompous.
...and just so KID.
"By the way, there is a small card for you, too," the woman reminded him again of her presence and Shinichi felt his face to grow hot. With trembling hands he took it and began to read once more.

I can see you blushing, Meitantei~
Not only I, but my doves adore you, too
Let's pay them our humble respect, shall we?
Where doves and rabbits meet
Just like detective and thief

Shinichi blushed only worse but turned to leave the store. Now with a huge bunch of roses in his arms he sure caught a lot of glances and if he was honest, he even liked it. Shinichi loved it to show off just a little, to pose a little with his overly wonderful boyfriend.
Once he set his foot into the park KID had held a heist in long time ago, his instinct led him towards the stature he once stole.
There, right at its feet, Shinichi saw a tiny rabbit hole under a tree next to it. Ha. Easy.
Shinichi crouched down and slipped his hand into it, only to be rewarded with a black box. A note stuck below the bow, again.

Don't open it until the very last second, Meitantei. But please, do enjoy my next riddle~
Time flows steadily
Cherry blossoms guide its way
An attempted theft of mine
And still you stole from me

Shinichi chuckled and bought himself a new ticket for the train. The attempted theft he had prevented. It was located on a bridge, down below a river decorated by trees filled with cherry blossoms. The place he had fallen in love with the cheeky thief.
Shinichi chased through entire Tokyo, discovering old memories and hidden treasures. When did the thief set up everything? Shinichi hadn't seen him gone a single second these days. By the time Shinichi made his way into the Tohto Tower, the sunset dived the whole area into a golden glim.
His arms hurted- presents over presents, from chocolate over a signed soccer ball to new mystery novels, plushies and more. Shinichi hadn't had the time to go home and give his arms a rest there, not like he wanted to leave anyway. Every single second he had a riddle in front of his nose and damned was he to not hunt the solution.

The platform above was empty... reserved under the name Kudo Shinichi. Where Kaito had gotten so much money from, Shinichi didn't want to know. Candles and rose petals guided his way towards the astonishing view onto Tokyo. This was the end of his journey.
"Meitantei."
Shinichi spun around, surprised to see Kaito in full costume as KID in front of him.
"W-what is the meaning of this all?" he nodded towards his arms full of presents. Kaito chuckled and motioned him to set them down which he did.
"Do you still have the black box?" KID hopefully asked and Shinichi held it up, smiling amused.
"You can open it."

Shinichi opened the lid-
Surprised to see a smaller, white satin box inside. His eyes shot up wide. No. KID wasn't going to do that to him. Tears began to dwell up inside his eyes and KID gently took the tiny device, opened it and lowered himself onto one knee.
"Meitantei... Kudo Shinichi... we are like fire and water. Earth and wind. Sun and moon. Detective... and thief. And yet, I love you more than my life."
Shinichi covered his mouth in shock, trembling.
"You stole the heart of the best Kaitou of Japan... and now you have to take responsibility. Kudo Shinichi, will you marry me?"
Shinichi stared at KID, unable to move or voice his overwhelming feelings. The ring was silver, beautiful golden ornaments decorated it- Shinichi immediately noticed the two tiny names the ornaments wrote. It was hidden, nobody would have noticed despite good detectives like Shinichi was.
Meitantei
Kaitou KID
It looked just like the perfect ring symbolizing Kaitou KID. Silverish white for the moon and his costume, a golden heart and speech, and the tiny pompous glim which gave away his mysterious aura.
KID looked up at him, doubt visible in his eyes. Why did Shinichi keep quiet?
"Shinichi...?"
That seemed to be enough for the Beikan to snap out of his frozen state.
"Yes!! Oh my god yes! Yes Bakaitou, yes!"

KID breathed out in relief and took Shinichi's hand into his gloved one, slipping the ring onto his finger.
"You are my Pandora... You give me immortality," he whispered, hugging his detective.
"You are my Apoptoxin 4869... You let me see the world through child's eyes and heart," Shinichi replied, equally husky.

I've written way too less fluff- I hope nobody got diabetes after reading this sugary sweet fluff~