。
She's still living off her parents.
Literal
[topic-は] still parent [genitive-の] shin [object-を] is-gnawing-on.
親のすねをかじる literally 'gnaw on a parent's shin' is one of Japanese's most colorful idioms for an adult child living off their parents' financial support. The image: a child too small to feed itself, biting the leg of the parent for sustenance. The expression carries a slightly judgmental edge but stops short of harsh — usually used self-deprecatingly or with mild teasing. すねかじり ('shin-gnawer') is the noun form referring to the dependent person. This idiom became extra-relevant during 1990s-2000s discussions of Japanese 'parasite singles' (パラサイトシングル) — adult children living rent-free with their parents.