Well damn. She'd noticed his interest in her hair. Lethe could probably suspect what sorts of interest he had in it as well. Less than noble interest in her hair, at that. Then again, that hair was distracting and keeping him from focusing on the meat of their conversation. A conversation that was surrounding Erebos at the moment.
He gave her his most charming smile and lifted a hand to ruffle through his own hair. He liked it to look intentionally mussed, as if he had just gotten out of bed and had only run his fingers through it rather than bothering with a comb. It was a very specific look, one that he'd perfected over the years.
“The story isn't that exciting. I was in a bit of a pinch with a mortal who had disrespected me. We had met earlier in Paris, so when Erebos came along and noticed I was distraught, he offered to help.” He didn't mention that it involved Erebos asking his daughter for help, or that it spurred a small earthquake specific to the mortal's location.
Loki's eyes darted down again to her lips, noticing her smile and taking pleasure in knowing he had made her smile.
Lethe was very ethereal and he wanted to touch her, to make sure she was real. It was in the way she looked, in the way she moved. Not just the hair, but the way she sat there, precariously positioned and balanced. It was in the color of her skin, the softness of her features and the look of her eyes. This goddess was as fluid as the waters of her river, no doubt. Soft. Otherworldly. Ethereal.