The 44-year-old singer revealed she ''got dizzy'' and went ''bright red'' when smooth-talking Harry, 26, started chatting her up and said she has heard from other women who've had similar experiences.
Chatting to her pal Eddie Benjamin for Interview magazine, Sia said: ''That little chap has some moves because he's got swag. He got me when I was like 35 or something, and he was 21. I know, I got dizzy.''
Eddie replied saying: ''That's amazing. Maybe he's just a flirty person,'' but Sia said: ''No, no, I've heard it from a lot of girls. He's got the smooth moves because he's a charming young chappy. But certainly I felt like I went bright red.''
Meanwhile, Sia recently proposed ''no-strings sex'' with her LSD collaborator Diplo, admitting he is one of only five people that she is sexually attracted to.
Speaking in a GQ profile of the DJ, she said: ''Much of our relationship is just being spent trying not to have sex so that we wouldn't ruin our business relationship because he's super-duper hot.
''This year I wrote him [Diplo] a text, and I said, 'Hey, listen, you're like one of five people that I'm sexually attracted to, and now that I've decided to be single for the rest of my life and I just adopted a son, I don't have time for a relationship... If you're interested in some no-strings sex, then hit me up'.''
Diplo later responded by telling PeopleTV: ''She's a loose cannon, and she does whatever she wants. She's spontaneous and insane, so I love her for that.''
When asked if he took her up on her offer, Diplo said: ''That's no comment. I love her to death and I value our relationship a lot more.''
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