She will never break her vigil of Nocturnal's Shrine and will spend day and night worshipping at the shrine. She prefers to sit on one of the benches, listening to the sermons randomly performed by Dhola from behind the lectern. At other times, she will get up and wander aimlessly around.
Francine Velain plays no notable role in the Nocturnal's Shrine Quest, though she does comment on your progress through it. If you speak to her before you begin the quest, she will say, "We are not afraid of the dark. The Night Mistress gives us eyes to see night's secrets."