One should not remain in a secluded place with a woman.
“It is stated in Srimad-Bhagavatam (9.19.17)
matra svasra duhitra va naviviktasano bhavet
balavan indriya-gramo vidvamsam api karsati
One should not remain in a secluded place with a woman, even one’s mother, sister, or daughter. Nonetheless, although one is strictly prohibited from staying with a woman in a secluded place, Narada Muni gave shelter to Prahlada Maharaja’s young mother, who rendered service to him with great devotion and faith. Does this mean that Narada Muni transgressed the Vedic injunctions? Certainly he did not. Such injunctions are intended for mundane creatures, but Narada Muni is transcendental to mundane categories. Narada Muni is a great saint and is transcendentally situated. Therefore, although he was a young man, he could give shelter to a young woman and accept her service. Haridasa Thakura also spoke with a young woman, a prostitute, in the dead of night, but the woman could not deviate his mind. Instead, she became a Vaisnavi, a pure devotee, by the benediction of Haridasa Thakura. Ordinary persons, however, should not imitate such highly elevated devotees. Ordinary persons must strictly observe the rules and regulations by staying aloof from the association of women. No one should imitate Narada Muni or Haridasa Thakura. It is said, vaisnavera kriya-mudra vijne na bujhaya. Even if a man is very advanced in learning, he cannot understand the behavior of a Vaisnava. Anyone can take shelter of a pure Vaisnava, without fear. Therefore in the previous verse it has been distinctly said, devarser antike sakuto-bhaya: Kayadhu, the mother of Prahlada Maharaja, stayed under the protection of Narada Muni without fear from any direction. Similarly, Narada Muni, in his transcendental position, stayed with the young woman without fear of deviation. Narada Muni, Haridasa Thakura and similar acaryas especially empowered to broadcast the glories of the Lord cannot be brought down to the material platform. Therefore one is strictly forbidden to think that the acarya is an ordinary human being (gurusu naramatih).”
Source : A.C. Bhaktivedanta Swami Prabhupada (2014 edition), “Srimad Bhagavatam”, Seventh Canto, Chapter 07 – Text 14