"Hey, dude." He gets the smile belatedly once he's sitting, though he can catch what preceded it before he does. "You know, long day of weird science, trying and failing to drum up enthusiasm for unusual flora among co-workers, day in the life. How's it going with you?"

She assumes he has something on his mind, though she's not averse to the company either way. He's been friendly, but it's a work trip and he's had his hands justifiably full. Still, she's curiously attentive to whatever he's going to pull out of his pocket.