。
There's nothing pretentious about her at all.
Literal
She [topic-は] at-all affected place [subject-が] doesn't-exist.
気取る (きどる) means 'to put on airs, to be affected or pretentious.' 気取ったところがない ('there is no affected aspect') uses ところ in its abstract sense of 'aspect, quality.' Combined with 少しも, this is high praise: she's completely genuine and unpretentious.