Them, from There

I'm pretty sure it's what Edward thinks is happening. I'm pretty sure Tedd can't think about this stuff at all. They certainly don't view Edward as having nuanced views, and we know that's wrong. Children under a certain age presume that bad things are their fault. (eight or so, and it has something to do with theory of mind.) Also note that Nanase's memories of first meeting Tedd -- their maternal first cousin who is the same age to the year -- are post-Noriko, if Nanase first met Tedd when Tedd wasn't talking. (Nanase canonically thought Tedd was mute. That's not a view Nanase could have formed if they'd known Tedd from infancy.) That's really weird. (It's less weird if the Verres have not always lived in Moperville, but everything we've got indicates that they have.) That implies there's a big something-or-other from Noriko's side of the family over marrying Edward. (If Noriko did marry Edward. "Have a kid with" and "marry" aren't the same.) What kept there from being any contact with the maternal relatives until Ted was... eight? nine? (I don't think it prevents Tedd from having issues about Nanase being exemplary; it might make the source more indirect.) We just found out that all magic users are descended from immortals. The family name is "Kitsune"; it doesn't seem at all unlikely there's an immortal back there that the family knows about, does it? So perhaps Noriko defied all sorts of family tradition to take up with Edward and have Tedd and the justification -- greater magical power -- failed (for social purposes at the time; we're finding out that it didn't, but Noriko doesn't know that) when Tedd didn't appear to have any magical ability. It'd be really interesting to find out what Edward and Mrs. Kitsune think happened, wouldn't it? Because we're obviously missing at least one important thing -- what Noriko thought they were doing -- and the general theme of incompetent parents doesn't make me think it's only one thing.

Keep in mind that Tedd only really knows that Noriko left because Tedd is defective. We've got the power-evaluator flashbacks, we've got some partial statements from Tedd who can't manage to talk about it, the whole "thought Tedd was mute" thing is Tedd's emotional trauma at being abandoned for not being good enough. Nanase is clearly good enough -- pretty, multilingual, athletic, powerful, social -- and Tedd clearly has issues about this. "Ugly cousin" isn't necessarily to avoid feeling attracted to Nanase; it might be to avoid noticing that Nanase is good enough and Tedd isn't. (We don't know what kind of memories Tedd has but "never coming home for Christmas" implies Tedd had some verbal understanding when Noriko left. That means Tedd has memories of how Noriko treated Nanase. It likely also means Edward is very, very angry with Noriko and possibly with Manase, too.) So my theory is that Edward Verres is sighing about Tedd being in female form not because of female gender presentation, but because it probably looks to Edward like Tedd trying to find a way to be good enough for Noriko by being more like Nanase. Any sensible parent is going to be worried about that because your kid trying to change themselves into someone else entirely so their other parent will love them is one of those "land war in Asia" classic blunders. (Tedd has misunderstood this, probably because Edward can't figure out a way to be sure saying something won't collapse Tedd back into complete social dysfunction and is saying nothing in consequence. Things are getting better, leave them alone.) We know almost nothing about that generation; I find myself wondering if Susan's mother was in on it; there's no reason the vampire-slayer tendencies don't come to Susan through the maternal line. It certainly looks like there was a group that had some kind of joint purpose -- protecting people from magic seems almost too unspecific -- and Noriko declared failure and ran away, but we don't know who was in the group. (We don't, for instance, have any backstory for Noah or why Raven is their guardian.) It strikes me that the character more likely to die is not Pandora but Edward Verres. Everything in the last however long has been acting to make an at-least-Tedd's-lifetime pattern of self-sacrifice pointless, and there's a whole lot of protectiveness and anger there. It wouldn't take that much for it to get loose.