Despite being an antichirst, Isabella's physical descrption is said to be quite angelic. She is naturally very beauitful, with pale smooth skin, light blue eyes, long eyelashes and blonde curls that hang just past her shoulders. However, when Isabella uses her demonic powers, her eyes are noted to change to black, and at extreme cases, blood can be seen dripping from her eyes like tears. She stands at 5'6, and has a slim figure.
Before her powers developed, Isabella dressed very girly, usually feminine clothes, nice shirts and skirts, and wore bright colours with different hairstyles to suit her outfit. However, as her powers progressed and Isabella became more aware of the supernatural world around her, her fashion sense changed dramatically, and she started to use many black jackets and few of pale colours and boots.
As for distinctive features, Isabella possess an unusal birthmark on her right arm which symbolizes the mark of the devil. She was born with this birthmark to help demons identify her as the antichirst.