The day started like any other, except for the slight crease in Nagumo’s brow. The kind of thing only someone close to him would notice. You had been keeping him busy all morning, dragging him across the city under the pretense of ‘needing help with errands,’ and while he smiled and joked the whole way, there was a quiet flicker of doubt in his usually unreadable eyes. He hadn’t said anything, of course. That wasn’t his style. But deep down, he had started to wonder if maybe you had forgotten what today was.

He’d pushed the thought aside. You, of all people? No, he’d decided to trust you, even as the sun began to dip and you still hadn’t said a word about it being his birthday. The final ‘errand’ led to Sakamoto’s convenience store. He raised a brow, his playful grin barely hiding his suspicion. “You need pork buns now? Again?” he teased, chuckling as you dragged him to the door.

But when you stepped inside, the store was pitch black. Nagumo’s hand instinctively hovered near the handle of his weapon, his senses twitching. His sharp eyes scanned the dark .. figures, shadows shifting until—Click.

The lights snapped on.

“HAPPY BIRTHDAY, NAGUMO!!” Shin shouted, holding up a banner slightly crooked on one side. Lu was perched on the counter, waving enthusiastically. Aoi and Hana were up front, beaming, and Sakamoto stood beside them with a massive cake that read “To the Most Annoying (But Loved) Assassin” in frosted red icing.

Nagumo stood frozen.

For once in his life—always being the one to catch people off guard, the master of deception .. was truly stunned. Then, slowly, a rare softness bloomed across the tattooed assassin’s face. A genuine, quiet smile touched his lips. He laughed, scratching the back of his neck. “You guys really went all out. I almost believed you forgot.”

That’s when his eyes landed on you and lingered. Sakamoto noticed. With a heavy sigh and a subtle nod, he ushered the others upstairs. Even Hana pouted but obeyed after her mom whispered something. Now alone in the quiet hum of the store, Nagumo stepped closer, still watching you.

“Thank you… for remembering and probably planning all of this,” Nagumo said softly. “I hope you’ll keep celebrating with me, year after year. Maybe next time without the near-heart attack, though.” He laughed again, but this one was softer, warmer. Reserved just for you. “Still,” he added, his dark eyes glittering with that familiar teasing gleam, “you did have me for a second there. Guess I’ll have to sharpen my senses.”