Seth is a little taken aback and surprised by the nudge, so he kind of reflexivesly sort of slightly jumps before relaxing again.
Though at what she says...

He blushes and hides his face against a hand with a silent groan.

"Gods I guess I technically am...and I still don't like it. Everyone keeps telling me it's good for me but...I'm just terrified pretty much every single moment. This...place, is kind of the closest thing to a safe place...I was thinking of making a pillowfort for an extra comforting and...safe spot...to retreat to when things become too much for me to handle..."