Yeah I have a feeling it could be a granuloma-- I just noticed that she likely also has a fungal infection (she is longhaired so I only realised it when I was bathing her earlier), which might be what triggered the reaction. Will bring her to the vet tomorrow as fungus is notorious for spreading quickly.I agree it is some type of lesion possibly caused by inflammation or a granuloma. She definitely needs veterinary treatment so I'm glad you will be going next week. Please keep us posted on her progress.