Her real name is Dulcinea, after her ancestress, Dulcinea Wilkes, the Archwitch.
She is a student at Larwood House. Like many plump, timid people, she finds boarding school a terrible experience - even without the extra burden of her unfortunate real name hanging over her. When the story opens, she has no real friends and is not taken seriously by the teachers.
She has a knack for describing things that sometimes comes out at inappropriate moments - such as the occasion when, as a guest at the high table, she finds herself compelled to describe what the food really looks like. This may be an expression of her own latent magical talent.