(Hey, just a short little heads up before this starts. This is actually a roleplay between a friend and I's that I've transferred over and it's ongoing as long as we keep it up. The parts in Sasori's POV are written by me while Deidara is by the lovely Deiendara on tumblr.)
Night was always the hardest time for Sasori. He used to welcome the night because it allowed him a quiet time to work on his puppets, but that was when he was alone. Now that he was in the Akatsuki he could be assured that there would always be a partner by his side to interrupt his quiet. Even the shallow breathing of sleep was enough of a reminder.
Night was also the perfect opportunity for him to examine or even turn his partners into puppets. They were immobile and couldn't fight back. It wasn't that he couldn't defeat his partners, but a battle meant potential bodily injury and it was always a nuisance to fix those injuries. There was also less of a chance for him to be interrupted and it wasn't as if the dark was a bother to him. Puppets didn't need light to see.
Deidara was no exception. Sasori had already turned two of his partners into puppets and Deidara's abilities were far more interesting than his former partner's. The only problem that Sasori had been running into were those mouths of Deidara's. It would be difficult to transfer their mobility into a puppet, and impossible until he fully understood how those mouths worked. He supposed that he could have paralyzed Deidara and examined his body right before the transformation. The result wouldn't be as beautiful if Sasori didn't have the time to make a proper design.
Which was why Sasori had Deidara carefully laid out before him tonight. A few minor modifications had been made to the puppeteer's preferred paralytic. It was much weaker now, non lethal, and now included a numbing agent to block out pain. He couldn't care less if his partner was in pain, but those mouths were so aggravating. If they felt pain, they would thrash about and get in the way of Sasori's operation.
The mouths on Deidara's hands were what Sasori was most curious with but they were also the most delicate. There was so little flesh around them that they would be difficult to work with. However, the large mouth on Deidara's chest offered the perfect opportunity for Sasori to examine their workings without risk of damage. His eyes flickered up to meet the blond's sleeping face once before he injected the numbing agent near the lip of the large mouth. The mouth twitched a few times before settling down and Sasori knew it was time. He tugged on a few strings and Hiruko picked up the scalpel and pressed it into Deidara's skin.