Conversation so far:
What is Tara Maclay's primary role on the show Buffy the Vampire Slayer?
Tara Maclay's primary role throughout the series is that of Willow Rosenberg's partner.
Do Tara Maclay and Willow Rosenberg form a relationship on Buffy the Vampire Slayer?
Tara Maclay falls in love with Willow Rosenberg.
Does Tara Maclay get Willow Rosenberg into magic on Buffy the Vampire Slayer?
Tara Maclay acts as a partner and guide in Willow Rosenberg's witchcraft.

Question: What keeps them grounded on the use of magic?
Self-contained rewrite: What keeps Tara Maclay and Willow Rosenberg grounded on the use of magic on Buffy the Vampire Slayer?