Rodeo's arm went around her to support her when she leaned against him, hooking behind her back and gripping her waist on the other side. It helped to hold her against him too, which he didn't mind all that much either. Her laugh made him laugh in turn, and he found himself chuckling roughly along with her.
When she got stern with him, though, he switched his expression. He donned the same expression a dog might take when his master spoke to him in a commanding voice-- penitent, but aware if his own cuteness and the power of a pouting lip. Though he knew it wouldn't work with Charlie, it was still an instinctive reaction whenever he was in trouble with a pretty lady. "Keeps things exciting, don't it? The library ain't all that far..." Rodeo paused, arching a brow slowly. "'Course, 'less you want me to stay the night," he said, lips curving into a playful little grin.