The alliance between the Germanic Star-Empire and that of the Elves was a strong one. So much so that the two empresses of the respective Elven subraces lived with Erich. If he needed to discuss any matters of diplomatic importance between them, he was quite literally only a few steps away.
This made some things easy, but also others more difficult. For example, Erich had fallen prey to the same old trick that Celestia used to confuse him in the previous timeline. Despite being on guard against it, Erich still found himself sleeping with Celestia and Sinaria, who both pretended to be their mothers.
It was an honest mistake, as the two women were practically clones of their mothers, and once alcohol was involved, it was easy to mistake them for the two most fearsome empresses in the galaxy. This, of course, caused Lunaria and Daelia to chastise Erich when they found out what happened.