Oh really? Did you just drop it after that or something?
I heard that Onodera's sister comes into play in the second season. Not sure what I think about that one especially since I just learned that she becomes part of the harem from you. Harems in itself are already hard for me to enjoy (Nisekoi's is ok, just ok), but too many people just make the show unwatchable for me. Unless they can really pull it off with the sister, which from you sounds like they didn't, I don't think I'll enjoy the arc.