It's kinda hard to tell what she wanted to do, but seeing her hand that low, maybe she wanted to touch his little ding-a-ling. The reason why I say that is because all she could think about was about the time she saw it, and then she even misunderstood when Ooyama said "Touch it directly with your hands". I really doubt she wanted to hug him, since is she was, she would "creep" higher, but the hand was going down low(even her eyes were looking low).