Matsya Purana — Yayāti in Amarāvatī-like Splendor: Devayānī Installed
तस्मिन्समागमे सुभ्रूः शर्मिष्ठा वार्षपर्वणी लेभे गर्भं प्रथमतस् तस्मान्नृपतिसत्तमात् //
tasminsamāgame subhrūḥ śarmiṣṭhā vārṣaparvaṇī lebhe garbhaṃ prathamatas tasmānnṛpatisattamāt //
In that union, the fair-browed Śarmiṣṭhā, daughter of Vṛṣaparvan, conceived for the first time—by that foremost of kings.
This verse does not address Pralaya; it belongs to a genealogical narrative describing conception within a royal lineage.
Indirectly, it reflects the Purāṇic concern with lawful progeny and dynastic continuity—key expectations of kingship and household life in royal ethics.
None is stated here; the verse is purely narrative and genealogical, with no Vāstu, temple, or ritual procedure specified.