1. In any criminal or juvenile delinquency action, expert testimony offered by the prosecution or defense which concerns the behavior of a defendant in preparing a child under the age of 18 years or a vulnerable person as defined in NRS 200.5092 for sexual abuse by the defendant is admissible for any relevant purpose. Such expert testimony may concern, without limitation:
(a) The effect on the victim from the defendant creating a physical or emotional relationship with the victim before the sexual abuse; and
(b) Any behavior of the defendant that was intended to reduce the resistance of the victim to the sexual abuse or reduce the likelihood that the victim would report the sexual abuse.
2. As used in this section, “sexual abuse” has the meaning ascribed to it in NRS 432B.100.