Eleutheromania

(TW: inferred self-harm and mentions of attempted suicide)

Fern is held captive by scientists wanting to study her wings, and she can't escape (she already tried that), the days bleed to weeks and she loses track of how long she's trapped..
One day she wakes up somewhere else, somewhere that's not cold or dark. Fern has been saved by a stranger named Ace who's going through his own pain.
Fern and Ace become slow friends, helping each other to heal their mental and physical scars, and to quench their thirst for freedom.