At first glance, Sionann Kelly is a typical Irish rose, down to the accent, the flame red hair, and a tendency to burn just from thinking about the sun for too long.  She initially came to the library looking for assistance (although she does not advertise what for), but has stayed on as a researcher.  She's a cultural anthropologist with a particular interest in ritual scenarios and the language connected with them - it makes her adept at tracking down particular fae heritages.  She was originally in New York on a work/study visa and has stayed longer than initially intended - she is now coming to the end of both her funds and her visa.
She doesn't tend to talk about what kind of fae she is, although she sees through the veil and shows little surprise at anything she encounters.  For those who can see fae in their true seeming, Sionann looks slightly ill.  Her skin is pale and marred with red marks and her eyes are a dull brown rather than the sparkling blue of her mortal form.  Her fingers have a slight webbing between them but the skin looks dry and chapped.