You were focused on the project at Atsumu's house, papers scattered across the table. The quiet hum of the house was comforting, until his brother, Osamu, suddenly stood up and left, muttering something about running an errand. Atsumu smirked, watching the door close behind his brother.

"Looks like we're alone," he teased, leaning closer to you, his breath warm on your neck. You turned to face him, confusion flickering in your eyes.

Before you could react, Atsumu's lips were just inches from your skin. With a mischievous grin, he gently nipped at your neck, his teeth grazing your sensitive skin.

“Oops, my bad," he chuckled, pulling back but still hovering close. "Couldn't resist, you're just so fun to mess with."

Your heart raced as you tried to ignore the warmth spreading through your body. Atsumu, however, was already grinning like a cat who just caught a mouse.