Roreil is highly subservient towards Nureha, telling off Mizufa for calling Adventurers "greedy" because Nureha had given them the iron-steel train. After Nureha runs off and her whereabouts are unknown, Roreil goes into a bit of a frenzy looking for her, demanding them to stop the operation in favor of finding her. He finds her in the Town of Saphir, which was being ransacked in the chaos caused by Operation Red Night. When he pleads with her to return to safety, she instead tells him to eliminate all the wyverns and Nightshades, and decides to cancel Mizufa's operation. Although he hesitates for a second, she reasserts her authority, and he quickly goes to obey her commands.
Nureha, being obsessed with Shiroe, likely does not think much of Roreil. However, his treatment of her can be interpreted as him being infatuated with her -- not a far cry, as Nureha took over Minami by seducing Lander nobles.
Little is known about Mizufa and Roreil's relationship. However, it is obvious that she doesn't care for Adventurers like he does, and she shakes off his admonition of her by retorting "Whatever you say, Captain of the Royal Guard."
It is possible that Roreil fears Mizufa slightly; when Nureha gives the order to cancel Mizufa's operation, Roreil hesitates until Nureha reminds him that she is the Chancellor of the West and her word is law.