Bleach: Sea of butterflies

Musashi sat at his small desk, his brow furrowed in concentration. His hand moved steadily, the brush in his grip sweeping across the pages in precise, deliberate strokes. The ink glistened faintly, shimmering with the faint energy of his spiritual power. Each word seemed alive, imbued with intent, as if the strokes themselves carried the essence of his Zanjutsu. The rhythmic scratch of the brush against paper was the only sound in the quiet room. 

Suddenly, an exasperated groan shattered the silence.

"Ahhhh, c'mon, Musashi! You can't just lock yourself in your room all day!" 

Musashi didn't turn but instinctively glanced at his bed. There lay Arasaka, sprawled out lazily, his arms and legs draped over the edges like a cat basking in the sun. His sharp eyes flicked toward Musashi, a mischievous grin curling at the corners of his mouth. "Look how beautiful it is outside! You should be out enjoying the day, not cooped up in here."

"I can, but later," Musashi replied flatly, his focus unbroken. "I need to finish this first."

"Boo! You're so boring." Arasaka flopped dramatically onto his stomach, burying his face in the pillow with a mock whimper.

Without even glancing up, Musashi asked, "How did you even get into my room?"

Arasaka ignored the question entirely, propping himself up on one elbow. "What are you even writing, anyway?" he asked, his tone shifting from playful to genuinely curious.

Still absorbed in his task, Musashi began explaining without stopping his work. "This is a book about Zanjutsu. Sai-sensei suggested I write one because no one else he knows uses the techniques I've developed."

---

**Flashback**

---

The memory was still fresh in Musashi's mind. He stood in the academy courtyard, facing Sai-sensei. Both had their blades unsheathed, their reiatsu rippling faintly in the air like heatwaves.

"On guard," Sai-sensei commanded.

The duel began. Their blades clashed with sharp, resounding strikes that echoed through the training grounds. Musashi's movements were fluid yet unpredictable, his strikes carrying a peculiar quality that threw off even the seasoned Sai-sensei. 

'This kid... his swings feel strange, like they're slipping through my guard,' Sai thought, narrowing his eyes as he blocked an incoming slash. 

Then it happened. He anticipated an attack from the right and shifted his guard accordingly, only for Musashi's blade to somehow appear on the left, stopping just short of Sai's neck. 

Sai froze, his eyes wide in astonishment. "I... lost," he admitted, lowering his sword. 

Musashi sheathed his katana with a sharp, decisive motion. Sai's gaze lingered on him, intrigued. "That kind of Zanjutsu... I haven't seen it anywhere. Where did you learn it?"

"I created it, Sai-sensei," Musashi replied calmly.

Sai's expression shifted from shock to admiration. Placing a hand on Musashi's shoulder, he spoke with earnestness. "Listen, Musashi. This Zanjutsu is yours, so it's your choice what to do with it. But I recommend recording it. Send it to the library. That way, you can inspire others and leave your mark for future generations. Your name as its creator will live on."

Musashi hesitated, looking down as he considered Sai's words. Finally, he looked up. "Sai-sensei, will you teach me how to write? I don't know how to create a book like that."

Sai smiled warmly at his earnest student. "Of course, Musashi. It would be my honor."

---

**End of Flashback**

---

"Heeeeh, how interesting," Arasaka said, his tone dripping with sarcasm as he stifled a yawn. It was clear he was only half-listening.

Musashi sighed, sensing Arasaka's disinterest. "Just wait a little longer. It'll be done soon."

Arasaka rolled onto his back, groaning dramatically. "This bed is getting cold, and I'm getting lonely! Hurry up!" he wailed, clutching himself theatrically.

"Don't say it like that," Musashi deadpanned. "Or I'll tell Sai-sensei about you sneaking out to mingle with upperclassmen after curfew."

Arasaka gasped, sitting up in mock outrage. "You wouldn't dare!"

Musashi smirked but said nothing, returning to his work. He was carving the final strokes onto the last page, pouring his spiritual energy into the ink like it was a blade slicing through stone. The writing had a sharpness, a clarity that mirrored his Zanjutsu itself. 

Finally, he closed the book and leaned back with a deep sigh. The tome was complete.

Arasaka, now dozing on the bed, stirred as Musashi nudged him awake with a light kick.

"Huh? What's going on?" Arasaka mumbled, sitting up groggily.

"The book's done," Musashi announced. "But I need your help coming up with a title."

Arasaka rubbed his eyes, grinning cheekily. "Fine, but you owe me some sake after graduation." 

Musashi nodded. "Deal."

Arasaka tapped his chin thoughtfully. "Whenever I face your Zanjutsu, it feels like your blade becomes a snake. Something to do with that, maybe?"

Musashi considered the suggestion, then wrote the title across the cover: *Fangs of the Serpent*.

---

The two headed toward the graduation grounds, where students gathered in small groups, chatting nervously. At the center, a raised podium stood, occupied by the academy's instructors and a few captains. Sai-sensei stood among them, his sharp eyes scanning the crowd.

"Hello, everyone," Sai-sensei began, his voice steady and authoritative. "Today, you will choose the division you wish to serve. Step forward when you are ready."

One by one, students approached captains to pledge their allegiance. Musashi and Arasaka watched quietly, observing the interactions.

"So," Arasaka said, nudging Musashi. "What's the plan? Who do we pick?"

Musashi frowned, thinking deeply. "We?"

"Of course," Arasaka said with a grin. "We're partners, right? I'll follow your lead."

After a moment of contemplation, Musashi decided. "The Sixth Division. Captain Kuchiki Ginrei."

Arasaka nodded in agreement, and the two approached Captain Ginrei. The distinguished captain studied them intently, his expression unreadable. 

'These two... their names have been mentioned before by the Captain-Commander,' Ginrei thought, pleased. 

"Welcome to the Sixth Division," Ginrei said with a slight nod. "Gather your belongings and report to the barracks."

Musashi bowed. "Yes, Captain."

Before leaving, Musashi approached Sai-sensei. "Sensei, the book is finished."

Sai's face lit up with pride. "Well done. Follow me. I've reserved a place for it in the library."

Musashi handed the book to the librarian, feeling a sense of fulfillment as *Fangs of the Serpent* was added to the archives. With that task complete, he joined Arasaka and the other recruits under Ginrei's command.

"Welcome to the Sixth Division," Ginrei said again, his voice carrying authority. "From this moment forward, you are part of the Division. Let's move."

(End of a chapter)