Kimi no Todoke 10 and revenge of the causative

Now that I learned to pick them up, I hear them all the time. For example, Kurumi says "おどろかせちゃった", or "made you startled" - odoro-ka (neg.base) + se (because odoroku is an -u type), and the shortening of shimau, I think. Indeed it's more common than passive.

BTW, Kurumi is starting to lose her cool. She knows that she's screwed.