Kyouka is interested in him, though, because of his display of power. After seeing what he did in Chapter 9, she says, "For the second time in my life, I'm trembling in excitement." I would attribute this more to her thrill at finding someone even more powerful than Meru, rather than her having any romantic attraction to Rintarou.
I'm not saying Kyouka won't develop feelings for Rintarou in the future (especially if her family requires her to find a strong man for a husband). At this point, however, I think it is more of her being deeply impressed by his abilities than anything else.
I'm far more amused at what Rino said to Rintarou, though.