Canto 3 -
Araṇya-kāṇḍa
Chapter 22: Khara and Others Depart to kill Rāma
Text 3.22.5

परश्वधहतस्याद्य मन्दप्राणस्य संयुगे।
रामस्य रुधिरं रक्तमुष्णं पास्यसि राक्षसि॥

paraśvadha-hatasyādya manda-prāṇasya saṁyuge
rāmasya rudhiraṁ raktam uṣṇaṁ pāsyasi rākṣasi

paraśvadha-hatasya = when He is slain by my axe; adya = today; manda-prāṇasya = and His breathing becomes slow; saṁyuge = in battle; rāmasya = of Rāma; rudhiram = blood; raktam = and red; uṣṇam = the warm; pāsyasi = you will drink; rākṣasi = rākṣasī.

Rākṣasī, today you will drink the warm and red blood of Rāma when He is slain by my axe in battle and His breathing becomes slow.

When His breathing becomes slow, His blood will be warm and red.1

1 Rāmāyaṇa-bhūṣaṇa: manda-prāṇasya alpa-prāṇasya. auṣṇyārtham idam uktaṁ rakta-varṇatvārthaṁ ca.