Ryuu was just as idealistic as Bell when she first became part of Astrea familiar and was a pure-hearted young girl about justice. However, her experiences with the war against Evilus during Orario's dark age which led to the deaths of many innocent people plus the death of Ardee made Ryuu question what justice really was. Coupled with her witnessing the death of her comrades by Juggernaut just broke Ryuu mentally and jaded that pure heart to abandon justice for the dark path of revenge only to find an empty feeling and be ready to accept death until Syr gave her a second chance to live.
Reading it in novels is one thing, but seeing it play in illustration from the games and anime form is another. Ryuu easily has one of the best character arcs in the entire series.
