It depends. Because if it's after Lo and B get together would it be before or after she comes out as an angel? And it's not like they wouldn't have a steady supply of blood. Billie and Clary can both get their hands on it if Lo isn't already feeding from Bullies and Zach will have Dahl, but Billie has a stash of human blood so she can contact Lucifer. Plus, you know, they have plenty of friends.

And I could see Molly avoiding Billoe, be kinda hard sometimes though... they have classes together ha ha. But at one point Billie would sit down and have an actual discussion of it came to it.

This is true. I had a little faith. Ha ha.