Valmiki Ramayana Aranya Kanda Sarga 43 Shloka 16
Original Shlokaसमाप्तवनवासानां राज्यस्थानां च नः पुनः। अन्तःपुरविभूषार्थो मृग एष भविष्यति।।3.43.16।।
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एषः this, मृगः deer, समाप्तवनवासानाम् after the completion of exile in the forest, पुनः again, राज्यस्थानाम् and established in the kingdom, नः for us, अन्तःपुरविभूषार्थः add beauty to the harem, भविष्यति will be.
After the completion of exile in the forest, when we are back in the kingdom, this deer will add beauty to the harem.