S3, E13: Yori returns to enlist Ron’s help in tracking down Sensei who has mysteriously gone missing. Kim’s jealousy gets the better of her and she can’t help but assume Yori is playing Ron when she smothers him with endless praise. Later we learn that DN Amy is behind the Sensei’s disappearance and was counting on Ron and Kim to lead her to their only suspect, Monkey Fist --- DN Amy’s one true love.