Englishnaturalness
noun
she was different—she'd lost a certain naturalness:
unselfconsciousness, lack of affectation, spontaneity, spontaneousness, lack of inhibition, straightforwardness, genuineness, openness, ingenuousness, simplicity, lack of sophistication, unpretentiousness, lack of pretension.
▷antonyms affectation, awkwardness, self-consciousness, pretentiousness.
naturalness Oxford Dictionary of English