She wants to share the bed with you

Lisandra's expression clearly shows that she is caught unprepared by your direct question. "My king, perhaps I... since tonight is a bit cold, perhaps I can warm your bed?" she stutters in an attempt to regain control of herself.

While such a ploy would have worked on you before this as you had, or rather still have a crush on her, now you're more wise and more importantly, not a virgin. Thus, you're in control of yourself, mostly. Even when Dobra did it when you're still one, you turned her away.

But you digress. There's an important issue at stake.

Do you take her words as they are and have Lisandra warm your bed with her hotness? Or do you try to solve the problem she obvious has and risk spending the night alone?