Valmiki Ramayana Ayodhya Kanda Sarga 39 Shloka 22

पापसङ्कल्पाः evilminded, युवत्यः young ladies, असत्यशीलाः infidel, विकृताः perverted ones, तथा also, दुर्ग्राह्यहृदयाः hard to read their hearts, क्षणमात्रात् in an instant, विरागिणः are devoid of affection.

Evilminded young ladies are infidels. They are of perverted nature. They are inscrutable. In an instant they lose their love (for their husbands).