Occasionally, Sasori can smell things.

It’s been a long time since he converted his body over to puppet form, his olfactory system included. Needless to say, it’s been an equal amount of time that he’s had to live with his sense of smell being royally fucked up. Sasori has never really minded, though. Sure, it gave him a mild panic attack to find out that he, of all people, had messed up in making a puppet. Within a few days, though, Sasori quickly found out how many smells he wasn’t missing. For one, it was amazingly easier to work on dead bodies when you weren’t whiffing up the scent of decomposition. Not to mention that some of the chemicals he used for poisons downright reeked. Plus, there weren't many good smells around the Akatsuki as it was.

Or, that’s what Sasori thought until he caught a hint of Deidara.

One of the things that frustrated Sasori the most was that he couldn’t control the moments of when he could smell. Sometimes, he felt like he was missing out on certain things, like that one time where he and Deidara got lost in the woods for three days, and they happened to stumble upon that waterfall. Both of them had been stricken by its sheer size, and all the foliage that surrounded it. Deidara was absolutely ecstatic with how loud it was and went off to explore the area. Sasori found himself sitting by the water for the next three hours, trying to place just what was missing for him.
It eventually hit him that he wasn’t able to sense the area by breathing it in.
Call it sentimental, or whatever, but something in Sasori had been crushed by that. He wanted to take in everything of his surroundings, not just the sight and sound of it.

Sasori had to commend his nose for when it did work, though. His sense of smell always seemed to kick in at the right moment, right near Deidara.
Deidara.
Something about Deidara-smell gave Sasori a head rush each time it hit him. He constantly tried to find words to describe it to himself, but nothing seemed perfect enough. The closest he had gotten to it was “earthy” and “full of air”, and there was no way that Sasori could deny that Deidara smelled natural; not at all fake, like most people do (or so Sasori became aware of).

His nose had been nice to him, and had been working since early morning, when he and Deidara were still awake. Sasori could tell that their games were drawing to a close as exhaustion closed in on Deidara for the night, but the reaction that the puppet nin had once the scents hit him was enough to keep them going up until this point. Sasori was now enjoying the smells by himself (Deidara had gotten up to pee), and was finding himself quite content.

Deidara’s bed had never failed to bring him joy in one form or another, and surely if the blonde knew how happy Sasori was with his pillow, he’d laugh. It was true, though. At that moment, Sasori wanted to do nothing else but keep his face buried in that pillow and soak up all the scents he could. He could tell that his nose was going to shut back down soon. There was an edging pinch he could feel that signaled an end to this.

A creak in the mattress soon told Sasori that Deidara had returned and by the way he seemed to be lying down, it would be safe to guess that the blonde finally wanted sleep. Sasori shifted his face away from that wonderful pillow to find his spot next to Deidara—he was quickly received—and took in a final deep breath, sucking up the last of any smells he could get.

Within seconds, all sense of smell was gone, and Sasori was left to ponder over any scents his mind could remember from the night, as Deidara fell asleep.