A Maledictus (plural Maledictuses) was a female individual who was a carrier of a blood curse that would eventually lead her to turn into a beast permanently. The curse was carried from birth and was passed down from mother to daughter. The beast ultimately transformed into could vary based on the curse.
It's unknown if a Muggle can carry the Maledictus curse. As yet we do not know if Claudia Kim's character is magical or not, as it has not been revealed, and it is possible that muggles as well as magicals may be afflicted.