This kind of t back is not suitable for 1st timer, she may feel something in between her asshole, you should look for the t back with wider coverage at the around pussy and asshole areas, so let her get used to it first, once she get used to wear it, then can she can slowly wear this kind of t back without feeling uncomfortable, I knew it because I wear t back for long time as well, I also started with this kind of t back with just a small string long time ago when I lived overseas, then the sales lady who is western girl shared this experience with me. Once you or your wife try it then you will know the differences.