Question about her paper for "absolute defense", is the paper also "absolute defense" or it can't be burned when it's active?
Maybe it's semantics super power, it's "absolute defense", not "invulnerability", maybe it's only truly absolute against things that are recognized as "attack", her tied up in lava technically isn't an attack.
So I see it going two ways, the paper will be slowly burned by the heat and she becomes vulnerable, or the paper can't be destroyed but don't identify the heat as an attack, so she's gonna cook slowly.