@Sep10trion
a) She might be an exhibitionist
b) They have no extra clothes with them
c) They don't know how to make crude clothing from forest materials
As for Alice...
Considering her brief change when she gave the keyword and still remembering the summoning spell, she either has brief moments of clarity, or she can control herself and is faking it
@Robbini It's pretty likely it's the latter since that summoning spell is a nonchalant way of getting rid of the protagonist, Who is even more dangerous than the hero who sealed her. Seriously, I'd be scared of him as well.
it might just be because I'm a pervert but there was something truely special about him trying to coax her into letting him stick his sword (handle) inside her. Kinda reminds me of one of the yokkora doujins...