"What did you do, study cheesy romance novels?"
The look on Sherlock's face makes it clear that yes, that is exactly what he did. Before supper they'd gone to see a matinee repeat of Casablanca, of all things. The remains of their picnic are scattered across the blanket. John's flat on his back with his arms crossed behind his head, content and sated.
"I wanted it to be right, John. Our first proper date."
John's face softens, smiling up at Sherlock. "You twit. No matter what, it'll be right. We've been living together for how long? I'm pretty sure you don't need to try to impress me at this point. Besides, I've already seen you naked. Trust me, there's no way I'm letting you get away from me."
Sherlock actually blushes and it might just be the most endearing thing John's ever seen. He reaches out, tentatively, to take Sherlock's hand in his, but before he manages, Sherlock's on his feet and packing up.
"Hurry, John, it's nearly seven, the sun's about to set. We're going to be late." Without any further explanation, Sherlock scarpers off, John following. When John finally catches up with him, he can't help but grin - Sherlock really did go all out for this, even if he has apparently been taking tips from Mills & Boon.