Valmiki Ramayana Ayodhya Kanda Sarga 9 Shloka 44
Original Shlokaत्वमायताभ्यां सक्थिभ्यां मन्थरे क्षौमवासिनी।।2.9.44।। अग्रतो मम गच्छन्ती राजहंसीव राजसे।
1 source checked for this shloka
मन्थरे O Manthara, आयताभ्याम् heavy, सक्थिभ्याम् with both thighs, त्वम् you, क्षौमवासिनी clad in silk garment, मम my, अग्रत: in front of, गच्छन्ती walking, राजहंसीव like female royal swan, राजसे shine.
O Manthara when clad in silk garment you walk in front of me with your heavy thighs, you look like a female royal swan.