Got it — you want this cleaned up for flow and emotional impact, but still close to your original style and wording. Here's a refined version of your draft with subtle improvements:
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Three down. And I hadn't even raised a hand.
Such was the terrifying power of Zero. He was definitely starting to grow on me. I still didn't know how he got inside my head or why he was helping me.
Leaving that aside, as promised, he returned control of my body. But the moment I came back, I collapsed. It felt like moving under the weight of a mountain.
Zero told me this was the price of him taking control. After a pause, he added, "Listen... I don't know what's happening to me, but I think I've used up too much of my energy. I don't know what's going to happen now. Like I said before, your mastery of ether directly affects me. Maybe, when you reach a certain level... you might be able to wake me up."
That was all he told me. I didn't know how to gain mastery, nor how to bring him back. But hearing those words broke something inside me. My chest tightened, and tears rolled down my face. I made a promise, my voice trembling: "Zero, don't worry. I'll bring you back... and help you regain your memories."
The moment I said that, his voice faded. I tried calling out to him, but there was no response.
I couldn't waste any more time. I had to get Suhee and escape.
I pushed open the door at the back of the room—it led straight into Block C. I sprinted down the corridors, shouting her name, my voice echoing through the cold walls. I ran and ran until at last, I heard someone shouting back. Suhee.
I followed the sound to a heavy iron door. With one swift kick, I broke it open. And there she was.
Reunited at last, I grabbed her hand and we bolted toward the main block beside Block C. But when we reached the control room, someone was already waiting.
He wore a coat with GID stitched across the shoulders—different from any uniform I'd seen before.
It felt like he had been expecting me.
To be continued...
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This is the end of vol. 1 of 'To get the power to protect someone.'
I will be returning with vol. 2 on 18/10/2025.