The 35-year-old musician dated the British model-turned-actress from June 2015 until September 2016, and despite their high-profile split, the duo remain on good terms, with St. Vincent describing Cara as a ''wonderful'' person.
The singer - who recently had Cara sing on her latest single 'Pills' - explained: ''I love her voice. She's one of the most naturally talented people I've ever met.''
Cara first found fame as an actress, but has subsequently turned her attention to acting, starring in a host of movies, including 'Paper Towns' and 'Valerian and the City of a Thousand Planets'.
Asked whether there's anything Cara cannot do, St. Vincent told Stella magazine: ''No. She's wonderful. I've never met a person more charismatic. I've never seen a person walk into a room and command the attention, not because she's trying, just because she burns brighter than everyone else. And she is just fundamentally a good person. She's uncorrupted by fame.''
St. Vincent and Cara, 25, ended their relationship almost two years ago, but the music star has insisted she doesn't harbour any ill-felling towards her ex-girlfriend.
In fact, St. Vincent - whose real name is Anne Clark - freely admitted she remains in love with the London-born beauty.
She confessed: ''I'll love her for ever and ever.''
Meanwhile, Cara previously revealed she considers herself to be sexually fluid.
She explained: ''Once I spoke about my sexual fluidity, people were like, 'So you're gay'. And I'm like, 'No, I'm not gay.'
''A lot of the friends I have who are straight have such an old way of thinking. It's 'So you're just gay, right?' [They] don't understand it.
''[If] I'm like, 'Oh, I really like this guy,' [they're like], 'But you're gay.' I'm like, 'No, you're so annoying!' Someone is in a relationship with a girl one minute, or a boy is in a relationship with a boy, I don't want them to be pigeonholed.''
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