The queen of the elves. She has never forgiven Svalin (er... another character. It would be silly to explain all this here.) for the fact that she fell in love with him. Her magic ability is limited, but she's pretty adequate at anything involving fire, hence the flame references.
A half-elf who has been exiled from the fairy country for several hundred years finds that it's not as perfect as he remembered it. Halflight Breaking is the title of the online comic that this applies to, hence the use of the phrase.