Lydia knew that he wasn't ever in a party mood, one of a lot of reasons why they really couldn't work together. Parties were her thing, a defining characteristic, and even if she really did prefer nights at home these days, she needed to hold onto that. Especially when other plans she'd had for herself weren't attainable and other things she wanted had to fall aside.
"Sure." She didn't have time. She knew exactly how late it was, hadn't really had the time to stop by in the first place but it wasn't like she had anyone waiting for her at the club. No midnight kiss for her and no one would know if she missed the countdown. Lydia paused long enough to just take her shoes off, trusted he wasn't leaving anything dangerous on the floor, Gibbs wasn't like that, before moving to climb into the boat with him. It wasn't graceful, and if it was anyone else she probably would have worried more about flashing him. She probably should have worried more. A part of her wished she did.
If she cared more, she wouldn't wind up in as many situations that inevitably became trouble as she did.
Settling with him, Lydia just took his drink right from his hand, didn't have any problem just sharing if that was the best that she could get, and lifted it slightly before taking a sip. "Happy New Year."