Valmiki Ramayana Ayodhya Kanda Sarga 38 Shloka 12
Original Shlokaतत्त्वेतत्समतिक्रम्य निरयं गन्तुमिच्छसि। मैथिलीमपि या हि त्वमीक्षसे चीरवासिनीम्।।2.38.12।।
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या त्वं such you, तत् एतत् all that, अतिक्रम्य having exceeded, मैथिलीं अपि even the princess of Mithila (Sita) also, चीरवासिनीं one wearing bark garment, ईक्षसे want to see, निरयं hell, गन्तुं to go, इच्छसि wish.
Having exceeded all that, you want to behold Sita in bark garment and thereby, wish for hell.