Lily looks at him the same way James looks at her.
It's not lust, exactly, though – because she knows what James wants from her –she just likes him. Remus. Remus, the werewolf. Remus, the werewolf who's fucking Sirius Black.
It's ridiculous, she knows, and not even only because of Sirius. He's a factor, of course – but Lily knows that Remus is bisexual, and so he could be attracted to her, but he isn't. He isn't, and Lily has to get used to that.
She sighs, and looks away. If he isn't going to look back, she has to stop looking.