As a bit of a loner and a ninja, Shiina is definitely very hard to approach and catch off guard. However, if one takes advantage of her weakness for cute things, it can be possible to distract her long enough to capture her. A strict tie to keep her from escaping is a must and wrapping her fingers in tape to keep her from accessing any hidden weapons is even more of a must. She does not easily reveal and weak spots but the backs of her legs have gotten the biggest reaction while a gag that highlights her eyes will often look the best on her. Give her something cute as a peace offering afterwards and she won't seek revenge.