I already posted this in one of the comment as a comment. But I'm gonna post it again cause I need you guys' opinion on this.
I think it's mostly time travel (second chance in life) story, Lee (Ernst) went back in time before the war, during the time when Rowen was still a prince. In chapter 4, when Lee woke up beside Rowen, Lee said that Rowen looked younger. On chapter 5, Lee said that the Black Lion (the mercenary group) would become great in future wars and that he didn't know that Prince Rowen was leading them directly. Rowen's hair color is different for disguise purposes (I think), since he is a prince that leads a mercenary group. As for the flashback, I think it's just...well, flashbacks or Lee probably just dreams about his previous (future) life. Anyways....this is just what I think.
I already posted this in one of the comment as a comment. But I'm gonna post it again cause I need you guys' opinion on this.
I think it's mostly time travel (second chance in life) story, Lee (Ernst) went back in time before the war, during the time when Rowen was still a prince. In chapter 4, when Lee woke up beside Rowen, Lee said that Rowen looked younger. On chapter 5, Lee said that the Black Lion (the mercenary group) would become great in future wars and that he didn't know that Prince Rowen was leading them directly. Rowen's hair color is different for disguise purposes (I think), since he is a prince that leads a mercenary group. As for the flashback, I think it's just...well, flashbacks or Lee probably just dreams about his previous (future) life. Anyways....this is just what I think.