I mentioned this last time, but Yuu's mom probably has a complex when it comes to her sister. She felt inferior to her elder sister who died. So probably, her memories of that inferiority complex was brought back up when her mom passed away. Emi might've been the favourite child that she wanted to surpass. She couldn't do it on her own, so she's forcing Yuu to do it for her.
Damiester
2020-06-27 03:05:45 +0000 UTC
Also, realise that the Dragon Knight leader was already betraying the team by contacting Shangri-la's masked guy. According to what Atori said in episode 8, the soldiers were all genetically altered or something. Though from what we can see, they probably aren't even proper living beings anymore lol.