Katy Perry reveals all about sister's shoplifting shame on TV

Katy Perry opened up about a family secret during a late-night TV interview on Monday (25Jun12), revealing her good-girl sister was once sent away to school in Arizona after she was caught with stolen lingerie.

While explaining where her love for all things Japanese started during an appearance on Jimmy Kimmel Live!, the pop star let it slip that her big sister was once banished by her religious parents for stealing from a department store.

The I Kissed a Girl hitmaker explained, "She's like the angelic figure; she's very perfect and sweet... She's sinned maybe once in her life and that one sin had her kicked out and moved to Arizona, because she stole, like, a bra and panty set from Macy's.

"She had to go and live with, like, another family... for a couple of months."

Perry then realised she had been too candid and added, "She probably doesn't like me telling you this on live TV."

And the star added, "She's such a good girl. She's the oldest child and she's, like, my warden; I'm the one that's doing all the sinning."

The story led to Perry revealing where her love for Japan comes from - while her sister was away, her parents opened up the family home to visiting students.

She explained, "My parents had an extra room... and we had exchange students from Japan come and live with us at our house and I was just, like..., 'Everything is Hello Kitty and it's perfect and it's clean and you eat with sticks.' It was so incredible watching them as a culture and I've been obsessed ever since.

"They're very polite... She (student) brought me these Hello Kitty chopsticks and I still haven't opened (them) and I was, like, 13."

But Perry is convinced her obsessive nature drove her Japanese friends away: "I asked to borrow one of their clothes (sic)... and they were very weirded out by it. I was like, 'It's so cute, all your little outfits, can I borrow one...' (I was like), 'I'm so obsessed with you, I wanna skin you and wear you like Versace!'"