Yui is one who is easy to capture either by asking her or taking her by force since she isn't very strong. When asking her, it's not that she'll agree to be tied right away, but she'll often distract herself in a fantasy, giving one plenty of time to bind and gag her. Her tights draw nice attention to her legs and that works well since the backs of her thighs are also her weak spots. Use a rope shibari to hike her skirt up and give her a heavy gag to get her to think of various other ideas and get her to struggle accordingly. She will eventually wear herself out and fall asleep though. That's when it becomes fun to untie her and make her wonder if it was all just a dream or not after she wakes up.