First chapter confused me to hell and back, but this one helps make a little more sense of things. My theory is that, first of all, Karin doesn't actually like Hiro's Dad. I think the tags may be a little misleading, though I guess it's impossible to know when the story is ongoing...

I'm wondering if Hiro's dreams are snippets of things that happened while she's asleep that she doesn't remember? Or her perspective on her Dad and Karin is warped because her dreams are making her interpret Karin as liking her dad. Who knows.