basically, edelgard is the dominant partner in you know what you call it and byleth is the submissive, so byleth calls edelgard "daddy" while in you know what u call it x2. hope this explained anything to you @Clueless1
Man, I hope Kuroko will be able to get herself a nice girlfriend at the end of the series at the very least. Although something tells me it would be a lukewarm ending if anything haha