She'd been telling a story to the camera when she went to scratch her eye, pulling her lid down and suddenly realising what she could see.
She says in the clip: "What?! That's my f***ing eye, dude!"
To prove her point, she then moves her eyeball around in its socket - the iris clearly visible from behind the skin.
The video has now been viewed 1.1 million times, with more than 161,000 likes and 1,300 comments.
It was actually another of her videos that went viral first - that one racked up 2.9 million views, more than 454,000 likes and several thousand comments - but her more recent one explained how she came across the bizarre epiphany.
Speaking to LADbible, 19-year-old @nev.lynn207 said it felt 'crazy' to go viral from the original video, adding: "The most recent one was found because I had gotten lots of questions on how I noticed it, and I knew I had a video so I found it and posted that as well!"
In fact, both videos have proven to be so mind-blowing to social media users, that they've prompted a wave of other people to try it out for themselves.
A large number of them have now also uploaded the results to TikTok in disbelief - many using the audio from one user's video, which says: "I just saw a video of a girl finding out her eyelids are transparent and I'm really pale so I wanna see if mine are too."
One user called @prettylittleidiot shared her attempt, saying in the caption: "The answer is yes."
Another called @hizzuc followed suit, writing: "I have no words."
According to an article by the Wall Street Journal, 80 percent of light passes through the eyelids, which sort of helps explain the bizarre phenomenon.
What really matters, though, is that you've already tried it for yourself while looking in the mirror... Haven't you?
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