Responses

they are not blood related! i think everyone in the story believes dietrich's mother gave birth to her before dying but that's not the case
if i remember it well, she is the child of the euclid family which is the rival family of the lagrange. i think her biological mother wanted to kill her or at least neglected her because she was not born with any special power or ability and that was a disgrace to the family so yeah
dietrich and anissa are not related
Wait a danm minute someone in the comments say the siblings are going to end up together?? Weren't they siblings or are they not blood related? The original FL is so basic nothing special