Ishana is possessed by the spirit, Kaaya, who can't enter the mortal world without possession. Nakki may also be possessed by a similar spirit. Her "brother" in spirit, Reivu, who is inside Nakki, my master... Maybe he didn't betray me..? Must continue chakra training. The other students need to be informed of Master Nakki's disappearance. I shouldn't tell them about the betrayal. The best I can say is that he is out on a mission and won't return for some time.