Never try to take Shiki by force, ever. She can be considered extremely dangerous to those who don't know how to approach her. While her shell can take a long time to come down, spending time with her and treating her well while earning her respect will eventually bring her to relent for a binding. Since she doesn't show much emotion, it can be difficult to find her weak spot, but along the back of her neck and her spine will often yield the most reaction. If, for whatever reason she needs to be taken by force, use any kind of gag but, more importantly, a blindfold to block her Mystic Eyes.