I believe it looks like she has two pairs of underwear on? Maybe i’m seeing things but it looks like she has a black pair underneath the tan pair
She likely had a second pair of panties on underneath.. looks like a fitting or dressing for set so the pair your seeing wouldn't be hers and for sanitary reasons models are usually expected to have a (nude thong) of their own on. But I have also had tape and/or moleskin applied to my junk for shoots/shows to avoid 'camel toe'. Much like 'chicken cutlets' (gel inserts) or tape for cleavage or stuffing male a model's tidy whities with wonder bread for that ken doll look.