First, the mistletoe appears in Lucy's apartment.

"You're not going to believe what Smitty said to me today," Tim says as he walks into Lucy's apartment after getting off a late shift with Metro. "He's trying to sell me some kind of juice cleanse. He-" he stops when he notices Lucy smirking at him. "What?"

She points above her, and he sees the mistletoe hanging from above.

He frowns. "Mistletoe?"

Lucy shrugs, but he can see a small smirk playing on her lips. "Tamara hung it."

That's a lie. He already knows it. Tim narrows his eyes at her in suspicion. "And?"

She puts her hands on her hips. "And? You're supposed to kiss me."

"You stood directly under it on purpose?" he wants to know with a quirk of his eyebrows.

"That's how it works."

"I think it's supposed to be that we end up under it, not that you wait for me under it."

"Are you going to kiss me or not?" she asks, hands to her hips.

He laughs, steps closer to her and extends an arm to reach for the small of her back. He doesn't pull her close, though, just settles his arm there, leans forwards, and gives her a purposely quick, soft kiss.

He pulls back to look at her and he can already see the annoyance and irritation lining her features.

He lets out a deep chuckle. "Kidding. Just kidding," he informs her, and several emotions wash over her face – confusion, relief, irritation (again).

She opens her mouth to say something, make some biting comment at him, but she never gets the chance before he captures her lips with his own and makes her forget everything.

Next, it appears in his office.

He doesn't know when she put it there, but he knows it had to have been her.

He comes back from a Metro team meeting and sees it hanging there, just over the doorway.

He chuckles to himself, thinking about her thought process – wonders if she thought about what would happen if someone else came and stood under the mistletoe?

"Hey."

He hears her voice and looks up, hiding the grin that threatens to spill when he notices exactly where she's standing – she's too damn predictable.

"Hey."

"How was the meeting?"

He knows she's playing with him, biding time until he'll look up and notice the mistletoe, but she should also know he's not going to say anything about it because two can play at that game.

"Good. Pretty quick." He does a purposeful double take at her. "Huh, you see King on your way in here?"

"King?"

"Yeah, she was just standing there a second ago," Tim laughs purposefully, like he's recalling a memory. Just in case she doesn't make the connection he adds, "Like exactly right there, then suddenly she noticed the mistletoe so she pointed it out -"

"She noticed the mistletoe?"

Tim gives a pointed laugh. He knows she'll understand the laugh, because he knows that she knows him, knows that she knows the laugh, and god it's even more fun to mess with her now that she can read him even better. "Oh yeah."

"Tim." She narrows her eyes at him, and they're in some kind of stalemate, both of them sure the other is messing with them.

"Hmm?" he pretends he's thinking about something else.

"Stop it!" she laughs.

"Stop what?" he asks as he stands, coming around the narrow space between his desk and the wall. "She was right there, said Hey, look, mistletoe! You know what that means."

"You're such a liar."

He clenches his jaw to keep from smiling. "You sure?"

She glares at him while studying his face, looking at him with dead certainty. "Yes."

He bursts out into laughter. "You weren't so sure."

"Yes, I was!" she says with a laugh of her own. "There's no way you kiss King under the mistletoe, for a hundred different reasons."

He smirks. "Just – on the cheek, that was all."

"God, I can't believe such a liar trained me, everything is tainted now."

He laughs, steps closer to her and leans in to kiss her – more than the teasing peck in her apartment, but gentle enough to be work appropriate. "Love you."

"Yeah, yeah," she gives a playful roll of her eyes. "You working late tonight?"

"No, I should be off around the time you are."

She nods, turns and heads through the doorway, then freezes for a moment before turns around and snatches the mistletoe with the help of a quick step up on a chair, causing him to chuckle.

"What are you doing?"

He catches her hanging mistletoe in his living room when she thought he'd be in the kitchen longer, catching her in the act and startling her as she turns to look at him.

This, right here, is one of the things he loves most about Lucy. He could have probably guessed it would be like this, being with her, but he'd only had glimpses before. The silly, teasing things she does for no other reason than to have fun with him.

And he does. He has fun with her. He finds her little games amusing.

Sometimes, what makes them more fun, is when he pretends to be exasperated by them (and sometimes, he really is).

"Hanging mistletoe," she says. He can tell she's caught off guard at getting caught, but she's falling into it by admitting it with confidence.

"Why are you doing it? I don't need mistletoe to kiss you."

"No. You just need an undercover operation."

He rolls her eyes. "Shut up."

"A pretend hook-up in an airplane bathroom."

"Lucy."

"Two first dates."

"Maybe I'll never kiss you again."

She laughs, reaches for him and tugs him close, one hand sliding up to his jaw. "We both know that that's not going to happen."

He reaches out and grabs her, pulling her to him and she squeaks out a cross between a laugh and a gasp as she's hauled into his chest, his arms circling around her instantly, one coming up her side to the side of her face.

"Well," she says, a little flushed and out of breath when they break apart. "That's why I did it."

He laughs. "You're exhausting."

"It's fun," she says with a grin. "Messing with you is fun. Maybe it's a kind of foreplay, now."

"Hasn't it always been?" he asks with a quirk of his eyebrow, and she bursts out laughing, a little thrilled at his admission.

Her eyes shine right back at his. "It's almost like you love me for this."

"It's almost like I love you, anyway." She grins as he rubs soft, soothing circles on her arm. "Hey."

"Hmm?"

"I'm pretty sure there's some mistletoe in the bedroom."

"I didn't-" she begins, then her stomach twists and flutters when she realizes his meaning. "Oh. Oh... yeah, we should probably check."