Barks at you

It’s a mix of me talking in general and game mechanic wise if she was an actual character within the game!

If Seren isn’t recruited into the black eagles house before the timeskip, you miss out on recruiting her just like with majority of the students. If you end up going the Crimson Flower route instead of Silver Snow, she shows up twice (once for sure but can show up again.)

During the timeskip, Seren becomes distant like she does in Azure Moon but even more, even living on her own as she completes mercenary jobs. During one job, she encounters some bandits and decides to search through their belongings and comes across a crest stone. She takes it of course—she knows full well what they can do but she takes it anyways. At first she intends to hold onto it so it doesn’t wind up in the wrong hands, but she keeps it anyways.

Anyways, the first time Seren is encountered after the timeskip is during a battle because she shows up midway and reluctantly aides her allies but steers clear of actually being next to them. (So probably like on the opposite side of the map) She fights the player and their units of course but doesn’t attack those who are part of Faerghus. In game, you can check her inventory and you can see a unique weapon; a sword she forged herself & you can see a crest stone in her inventory. Seren can be defeated here or you can allow her to flee if you just ignore her.

If Seren escapes, then off screen she goes into hiding again and she eventually uses it as a last resort during a job; she doesn’t think anything terrible would happen since she’s not necessarily human so she assumes she wouldn’t be affected by it but oops she’s wrong. Yes the stone works, but after some time she ends up transforming into a demonic beast (similar to how Miklan does) but it seems to be a mix between that and a giant wolf as seen in game.

In a later battle, she ends up appearing in the middle of the fight and attacks anyone regardless of them being her ally or enemy. She has very minimal control over what she’s doing (which might have to do with her not being entirely human but yeah); she attempts to speak but her voice is very distorted and it’s hard to understand her. If in game; you can view her inventory and she has the crest stone and the same weapon as before!

And if u do defeat her, you get her sword and possibly the crest stone; but for sure you get her sword😁

You can ignore her the whole fight and let her be but that just means she’s stuck that way so yeowch

Basically if she WAS in game, it’s not outright said it’s her, but just connecting the dots with the inventory would be enough to be like ohhh is that Seren??