Why does Aversion provide a serious malus to our diplomatic balance here?
As I understand it, Diplomatic balance represents how equitable both sides think an interaction are. A malus for us means that we think we owe an obligation, whilst the other side thinks they are owed a debt. I don't see how either of those matches with aversion. If we don't like the Sendai, you'd think we feel we owe them LESS, not more. Conversely, unless the Sendai KNOW that we don't like them (and I don't see why they should), I don't see why they would think we owe them more, either.