The artist is definitely spoiling Kei's role early in a way that didn't happen in the novel. What the hell are these expressions....
@greatninja3
What the hell? He was never romantically involved with Romantica. They were companions in the same squad in the Shadow Labyrinth, and she was possibly the last friend that Desir had to watch die. That's why he cares so much about seeing her alive at the beginning. Don't just make up that they were in that kind of relationship.
At the end of the novel he even goes as far as to confirm for the audience that he never had romantic feelings for *anyone* before. He was too focused with saving the goddamn world.