[it's a little of both, actually. surprise: Magilou has a weakness for families!! and knowing now how important Falchion was to Lucina-- knowing how that sword meant more to her than her life simply because it was a family heirloom, a symbol of her having a place to belong-- meant that Magilou could empathize with its loss extremely well]

[but there's also desperation there. a grab for agency, a grab for some kind of damn choice now that she's quickly realizing those without roles such as her were never given one in the first place. and that's why she bristles at being told she can't]

What's it matter, anyway? I told you-- I'm selfish.

[she stands up now, twirling the knife around in her hand with some dexterity as she tosses her now-lean ice cream stick into the bonfire]

I'm going, and whether it's for myself or Lucina isn't important. You can come with me, or you can stay behind. Your choice, Trickster.