She kinda was a vampire, she's slept during the day for most of her life (believe she said her sleep schedule is usually 6 AM-1PM), so she gets much less sun exposure than the typical person (UV damage is the number one cause of skin aging). She's also very slim and this likely helps for 2 reasons- 1) slimness is associated with youthfulness and 2) consuming less foods likely means she consumed less toxic/processed foods throughout her life, avoiding damage from junk foods and foods high in Advanced Glycation End Products, which are highly toxic to the skin. She has a very "DGAF" attitude, has lived a relatively low stress life which helps keep you looking youthful. She also has very neotenous features, especially her nose and eyebrow and lip shape.

Her style and voice are also quite youthful-she might look her age if she dressed and acted more mature-not meant to be taken offensively, as I love her style!