"My family lineage can't be discussed without discussing swordsmen"
This feels like a subtle hint (since she didn't mention how they were related to swordsmen, though it could be handwaved as just their magic) that her family was responsible for the downfall of the last sword saint or something along those lines, since I doubt that Seira's lineage is actually a "war criminal" like was mentioned. Getting vibes of something like "we killed your ancestors and framed him via our sword magic, which people took to be his swordsmanship" or something.