Kasumi is a ninja who is used to people following and stalking her, so it is almost impossible to get the drop on her under any conventional circumstances. She will, however, accept an escape challenge as part of her personal training, so it's best to approach her with that excuse. She also tends to wear her hair in a few different styles so make sure to incorporate that into how she's tied. If her hair is down, emphasize her chest. If she's wearing a ponytail, emphasize her back. Make sure to give her a strict tie no matter what, as she can and will get loose on her own in due time.