"Is my new librarian a Watcher?" she asks Sherlock the day after Mr. Giles joins the faculty.
"Shall I be optimizing for arranging to fling you into walls or something instead, or does it not matter either way? Is that going to be - awkward?" she asks. Slowly. Awkwardly.
"Will it be awkward," he muses. "Between the two of us I'm not sure I am the one best equipped to answer that question. If you would rather not make it your business at all, you needn't."
"So you're not going to make a big deal about it and you're just letting me know FYI," says Bella. "...Okay. That is a reasonable behavior." She resumes walking. "You didn't answer about the flinging-you-into-walls alternative."
It occurs to Bella to ask as they approach the crypt, "Would anything meaningfully improve about the practicing if I took off the crucifix? I don't know how much of your attention not reacting to it takes, and there's always some possibility it'll pop out of my shirt and hit you in the face or something."
"...It could make a slight difference," he allows. "It doesn't take up very much of my conscious attention, but I am always aware of it."
"So it's probably not hampering your ability to challenge me yet but it could do so in a few days if I keep improving at this rate, which is admittedly optimistic because low-hanging fruit is called that for a reason," Bella concludes. "Okay. I can take it off for this purpose after making reasonably sure that no one has tried to move into your crypt or anything."
She unhooks the clasp of the crucifix and puts it with her messenger bag.
"Surprise me," she says.
Until they've done nine of them and then on the tenth, full of new edits, she does slam him into a wall. (She's also bleeding in two places and she's got a ringing headache, but Sherlock violently encounters that there wall.)
"My head hurts. I need to start bringing ibuprofen with me," she says, sitting down heavily. "Aaah. Thanks though."
"It's - flattering? Unprecedentedly flattering. I mean, random people utter innuendo all the time, but it's not based in any genuine regard, whereas I'm pretty sure yours is." She pokes at her scalp gently, wincing when she reaches the point of impact and maps its borders.
"I have a genuine regard for you on a number of levels. The fact that you can throw me into walls is only one among many."
"Many? Okay, at the risk of sounding - completely accurately - like I am fishing for compliments, I count throwing you into walls and my talent for analysis. That's not many."
He shrugs.
"And what with all of this bodyguarding and martial instruction, I am becoming somewhat attached to you."
"A successful fishing expedition," says Bella, ineffectually hiding her faint blush with her hair. "Charlie would be so proud."
He puts on a perfect imitation of Bella's voice and accent and tilts his head up slightly, with a wide-eyed, excessively innocent look. "Hi, Dad! Tonight a vampire flirted with me, and I encouraged him shamelessly!"
Now in Charlie's voice, with a sterner expression cut by a hint of wistfulness: "Sure I can't shoot him again?"
"Should I not encourage you shamelessly? I could stop. Or induce shame. I don't want to be mean or anything."