The next morning, as they were flitting through the trees with Sasuke strapped securely to Kakashi’s back once more, Sai turned to Sasuke and offered a pleasant smile.
"I’ve read that giving someone a nickname fosters familiarity and friendship between the two parties. Is Manpain acceptable to you?"
Naruto ran into a tree. Face first, ran into it, and then slid all the way down like a bug on a glass door.
"What," Sasuke said, and again, it was really not a question.
"No? That’s all right. I’ll think of something better."
The faintest trace of horror crept across Sasuke’s face at the concept of ‘better’. From the ground, Naruto’s braying laughter came up through the branches.
"GURK. HA. HIS FACE. SAI. YOU’RE THE GREATEST."”—Uchiha Sasuke, Hatake Kakashi, Sai, and Uzumaki Naruto, ‘Ricochet’ by Strix 4 (FanFiction.Net)