Valmiki Ramayana Bala Kanda Sarga 48 Shloka 18
Original Shlokaऋतुकालं प्रतीक्षन्ते नार्थिनस्सुसमाहिते।1.48.18 सङ्गमं त्वहमिच्छामि त्वया सह सुमध्यमे।।
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सुसमाहिते O Highly beautiful one (with symmetrical limbs), अर्थिन: passionate seekers, ऋतुकालम् a period when women become fresh after menstruation, न प्रतीक्षन्ते would not await, सुमध्यमे O Woman beautiful waist, अहम् I, त्वया सह with you, सङ्गमम् union, इच्छामि am desiring.
'O most beautiful one those overtaken by passion would not await the completion of the menstrual period (favourable for copulation). O woman of fine waist I desire union with you.'