Episode 3 of The Glimmerbrook Witch shows how far Willow has come in her magical endeavours.
Fire played an important part of Willow's previous incarnation where she would put the Sim to sleep with a sleep potion and then set them on fire. Her fascination with fire continues in her present life, especially as she has now learned the spell "inferniate".
This spell does what it says on the jar (or in this case, the spell book). Of course, as with everything in life, you reap what you sow and this extends to Sims.
Any spell can backfire and unfortunately for Willow, it does. However, this lady's not for turning, or should I say, this witch is not for turning because no matter what happens to Willow, albeit through her own deeds, she will not be deterred from her evil ways.
Here is a clip of Episode 3 of The Glimmerbrook Witch: