Demi Lovato shows off major cleavage in swimsuit selfie: 'Why not?'

Forget "Cool for the Summer," Demi Lovato is looking hot!

The 24-year-old singer continues to flaunt her rockin' swimsuit body on Instagram, this time posting a cleavage-baring selfie paired with the cheeky caption, "why not?" (Not to be ignored: Lovato's perfectly arched eyebrows and chic sunnies. Slay, girl!)

WATCH: Demi Lovato Talks Soulful Music and Past Career Struggles

Meanwhile, Lovato is proving she's a pop star who can do both -- earning herself a slot on Time's 2017 Most Influential People List for her work in mental health advocacy.

"Demi Lovato is a remarkably talented artist and performer," Ariana Huffington writes in tribute to the singer. "But her courage, honesty and willingness to use her own experiences to help others are what make her a true star."

WATCH: How Demi Lovato and Mike Bayer Are Making Mental Health Mainstream

Last month, Lovato celebrated her fifth "sober birthday" and opened up about the milestone to ET.

"It feels amazing," she said at the 2017 Kids' Choice Awards. "All I've been doing is focusing on bettering myself. It's been quite the journey, but it's well worth it."

The "Confident" singer gushed that her "life is in a really good place right now," revealing a sweet tidbit about her new relationship with Guilherme Vasconcelos: "He makes me laugh."

See the interview above!

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