Cirie didn't have suspicion on herself but Christian was making mistakes - big mistakes. Furthermore, Christian's nervousness resulted in him talking way too much. There was a time when Christian was talking with, I think, 3 faithfuls and Arie on some couches in the castle as they were trying to figure out who the traitors could be. During that conversation, Christian made an off-handed remark that anyone could be a traitor, even Arie (pause), even you (the person he was talking to), turned to the next person implicated them and lastly, implicated even himself. Afterwards, during the confessionals, Arie indicated that Christian was acting reckless and he felt as though he (Arie) and Cirie should be concerned. In short, Christian wasn't acting trustworthy/loyal to the other traitors.