dripping-diamonds
Mitsuki remembers the exact day Katsuki learned the word mine and decided it applied to everything soft, green-eyed, and freckled.
Izuku (tiny, earnest Izuku) in the sandbox is a lopsided castle with a plastic All Might flag. Katsuki stomps over, palms sparking, and plants himself in front of it like a guard dog.
"Mine," he declares, pointing a stubby finer at the castle.
Izuku blinks up, eyes huge, and offers a shovel. "Wanna help, Kacchan?"
Katsuki's cheeks go red. He snatches the shovel, sits, and starts digging a moat.
Mitsuki hides her laugh behind her coffee mug. Already whipped, brat.