One June morning, Brainy wakes up late. He fumbles to grab his glasses from his bedside table, and changes into his dayclothes. He's in that awkward stage of adolescence all smurfs hit in their late 130s- purple spots of acne dotting his face, waiting for a growth spurt that for him, would never come. His voice cracking.
"Brainy!" A voice calls. "Y'wanna come out 'n' play smurfball with us?" When Brainy hears Clumsy's voice, he's struck with... some feeling. He doesn't understand it. He rushes to the door, flings it open, runs out to see Clumsy without a second thought. Clumsy has hit his growth spurt already, tall and gangly and waiting for the rest of his body to catch up to his legs. He's not much to look at, but Brainy thinks he's the most beautiful thing in existence.
Oh smurf, Brainy thinks, except it's not smurf but another word, but Papa Smurf says swearing is unsmurfy, so he'd never repeat it out loud. I think I like him.
Of course you like him, you'd say. You're his best friend. But Brainy was young, unsure of what "love" really was, and "like-like" was the closest he could think of without being brash. Brainy's team lost the smurfball game that day, partially because Brainy kept getting distracted and stealing glances at Clumsy, whose skin was slick with sweat from the summer heat and the exertion of the game; and partially because having Clumsy Smurf on your smurfball team automatically makes you lose.
For a while, Brainy secretly pined over Clumsy. He stumbled over himself, obvious to everyone except Clumsy; wrote books and books of love poems; doodled "B+C" in a heart in his notebooks. It faded away, though, and by the time Brainy was 180 he was just best friends with Clumsy again. Mostly, if he didn't think about it.
Clumsy, bless him, had never even known such a crush existed.