Valmiki Ramayana Yuddha Kanda Sarga 121 Shloka 18
Original Shlokaन हिशक्तःसुदुष्टात्मामनसापिहिमैथिलीम् । प्रधर्षयितुमप्राप्यांदीप्तामग्निशिखामिव ।।6.121.18।।
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सुदुष्टात्मा evil minded, अप्राप्याम् inaccessible, मैथिलीम् Mythili, दीप्ताम् glowing, अग्निशिखामिव like flaming fire, मनसापि in thought also, प्रधर्षयितुम् exhibiting, न हिचशक्तः not possible
"It could not be possible for the evil minded Rakshasa to access or lay thoughts on Mythili who was glowing like flames of fire."