Have to say, as much as I love Kiriha, I am happy that she was punished because of her "go with the flow" way of thinking, she is to dominate when it comes to her ideas but she doesn't really support all that she said with real substance, the point that Shinobu is really important because it shows that they cant simply bulldozer their way out of things when there is other methods that are better for them and those around them, more so when they will need much more finesse to defeat Kazuya's mother, she isn't the type of enemy that they will defeat with luck.
And one last thing, I know I am the major minority but I liked this arc, I understand what made so many hate it and I won't argue against this feeling but I really like this adventure, it was stupid in many points but for me, it was satisfying ( obviously because Hamada-sensei upped his ecchi game 500% XD ).