Treatment

Nami and Luna gazed at Number One with complicated expressions but they didn't comment anything besides leaving a kiss on his head. The fact that he had to go through so much pain in his life would never sit well with them. 

They didn't question him about his decision either as they heard a knock on the door right after. The servants finally arrived while pulling a big tub through the door and placed it in the middle of the room.

'Protect me while I'm gone. I will go make some pills,' Number One informed Nami in his mind as the servants began filling the tub with water and he slipped away into his heavenly space. 

His decision was definitely selfish but Number One never claimed to be a good guy. Saving that man would prove his skills to the world and he could achieve his goals much faster. Even if they wanted to spare his brother of pain, Number One would still try his best to save his life.