Love
"You know."
"..."
"...Ahem."
"Mh."
"Heh. I know some people use 'love' conversationally, just when talking to anybody."
"...Well done, Lestrade, would you like a lolly?"
"Well. John uses 'love'."
"Really excelling at the basics, Graham."
"But he doesn't seem to use it for just anybody."
"Please, let's reach your destination before this body fully decomposes."
"He only calls you 'love'."
"Dear lord. And they recognize you as one of their best."
"So are you two a thing, then?"
"John and I are many things. None of which we're trying to keep secret, though it seems we wouldn't have to try hard to keep anything from you."
"Ok but seriously now, Sherlock. You two?"
"Hhfh. What we are is not something which can be so simply labeled."
"...Are you happy?"
"..."
"Oh hell, you're blushing."
"I am doing no such thing."
"No but Sherlock I'm really glad for you. Honestly."
"Mh."
"He treats you well?"
"Dear lord, Lestrade."
"No it's just I worry about you sometimes. You were in such a bad place when we met."
"Do you expect me to accept less than the best?"
"I -...Sunshine."
"..."
"I know you don't think much of yourself sometimes. I know the way people have treated you has made it hard for you to believe you deserve anything, let alone the best. I think maybe you'd be willing to accept less than the best if it made you feel any sense of belonging. Not all belonging is good belonging."
"He treats me well, Greg."
"Good. Good. But if anything ever comes up -"
"It won't."
"Right. Alright then."
"Alright then."
...
It's only a short time - and several rapid-fire deductions - before John returns from interviewing the victim's cousin. "Think I got everything she has. Ready to go, love?"
Sherlock looks up from his phone, furrowed brow smoothing, lips twitching into the subtlest smile. To anyone who doesn't know to look closely, it's nothing. To a certain Detective Inspector, now self-appointed protector of Sherlock's heart, it's assurance. Greg turns to direct a wandering officer, and hide a smile of his own.