It may just be me, but when I read a story that involes a couple, I hate when every word out of their mouth when speaking to each other is "baby", "sexy" or "sugarpants" etc when referring to each other. Once in a while is okay but I hate when they overdo it. Overly loveydovey blah.
I like Dialga and Palkia as a couple, but I wouldn't have Dialga call Palkia "sexy" or "baby" in every sentence he says to her. lol