Loving the look but I had to do a double-take on that foot. 👀 Some people suggest it's the heel of her foot, which kinda tracks as long as you accept that the perspective on the foot is super weird.
A quick glance suggests that this artist has a reasonably extensive history of drawing dating back to 2013 according to HentaiFoundry. Their Twitter profile is sparse on WIPs but has a few as far as back as 2019, so I'm inclined to give them the benefit of the doubt and say it's just some jank on their part.
I totally appreciate the second opinion though; glad it wasn't just me that thought about it.