The singer-songwriter, 21, took to her Instagram with a slew of throwback photos which she'd simply captioned: "some old," and included a series of shots that showed off some candid fashion moments, snippets from tour, and funnier outtakes with friends, plus a visit to the Museo Nacional de Bellas Artes in Argentina.
In one of the photos, however, the fourth slide in the compilation, she left fans stunned with a bikini photo, featuring a person in a nude-toned string bikini lounging in a tub, showing off a massive tattoo on their thigh.
While it's left ambiguous whether the person posing is actually her or someone else, since the face is hidden and the ink differs from her popularly known dragon tattoo on her hip, many of the commenters on her photos believed it could be hers.
Her fans left comments on the post like: "4th slide has me unconscious," and: "Hold awnnnn, the bikini pic???" as well as: "I'm on my KNEEEEEEEE CAPSSSSS for the 4th."
Others commented on the general slew of photos with: "I always wonder how chaotic her camera roll is," and: "Imagine Billie when we only had those throw away kodaks. I bet she'd have luggage full of em."
In a photo posted last week, Billie finally revealed her back tattoo after fan speculation grew on TikTok. Dressed in a simple red graphic tee and low-rise jeans, with her red hair tied in a braid and pushed away, an intricate patterned design poked out from behind the shirt, stretching from her back to her neck.
While she hasn't yet revealed what the exact tattoo is, some of her followers on social media have speculated that it could be a second dragon tattoo, similar to the one on her hip.
A fan commented on that photo: "The day she does a tattoo reveal I fear I will stop breathing," and another also added: "BACK TATTOO REVEAL PLEASE."
Billie has mentioned being a lot more shy when it comes to showing off her more revealing ink. Based on prior interviews, she has a tattoo of her surname, Eilish, across her chest, three fairies on her hand, the large dragon tattoo running down her hip, plus the unspecified one on her back.
The Chinese dragon, spanning from her hip to her upper thigh, has never been seen in its full form, although she did show off a large part of it for her cover shoot for British Vogue in 2021 and now her latest photo.
In an interview with Vanity Fair, she'd previously confessed that she didn't want any face tattoos, emphasizing a preference for ones "barely anyone can see."
In the 2021 edition of the same interview, she opened up about her three tattoos at the time, saying of the surname on her chest: "Yes, I love myself," and called the dragon her "big boy."
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