Valmiki Ramayana Sundara Kanda Sarga 10 Shloka 14
Original Shlokaशुशुभे राक्षसेन्द्रस्य स्वपतः शयनोत्तमम्। गन्धहस्तिनि संविष्टे यथा प्रस्रवणं महत्।।5.10.14।।
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स्वपतः sleeping, राक्षसेन्द्रस्य lord of rakshasa's, शयनोत्तमम् magnificent couch, गन्धहस्तिनि elephant in rut, संविष्टे is sleeping, महत् great, प्रस्रवणं यथा like Prasravana hill, शुशुभे looked lovely.
While the lord of demons lay asleep on the magnificent couch, he looked like the Prasravana hill with its elephant in rut.