Śrīmad-Bhāgavatam · Text 9.10.22
Who is speaking and story frame
रामस्तमाह पुरुषादपुरीष यन्न:
कान्तासमक्षमसतापहृता श्ववत् ते ।
त्यक्तत्रपस्य फलमद्य जुगुप्सितस्य
यच्छामि काल इव कर्तुरलङ्घ्यवीर्य: ॥ २२ ॥
rāmas tam āha puruṣāda-purīṣa yan naḥ
kāntāsamakṣam asatāpahṛtā śvavat te
tyakta-trapasya phalam adya jugupsitasya
yacchāmi kāla iva kartur alaṅghya-vīryaḥ
Lord Rāmacandra said to Rāvaṇa: You are the most abominable of the man-eaters. Indeed, you are like their stool. You resemble a dog, for as a dog steals eatables from the kitchen in the absence of the householder, in My absence you kidnapped My wife, Sītādevī. Therefore as Yamarāja punishes sinful men, I shall also punish you. You are most abominable, sinful and shameless. Today, therefore, I, whose attempt never fails, shall punish you.
Read Śrīla Prabhupāda's purport on Vedabase.io