Fangs would be fine to keep, since other vampires in the game have retractable fangs! And yes, the Aurora could absolutely allow Jessica to drink animal blood as there would not be any synthetic blood from her canon world available — and to ensure the stability of the game with only a limited number of humans in game. Feeding on other characters is allowed, provided OOC discussion is had between players.

In addition, I'll post links to some applications of other vampire characters already in game to help with how they function within Singillatim.

— Astarion
— Louis de Pointe du Lac

If you have any further questions, please don't hesitate to reach out!