It's netorare that's all it really is it's how they show the girl has completely fallen and sex is all she cares about.Actually why I'd hate the story ending with the ships like they're shaping out to be. Shinobu was always considerate, Yuma just took what he wanted. Also Sakura was more verbal with Shinobu while so far in all they've shown us with Yuma it's just the same forced out moans.