Matsya Purana — The Greatness of the Vibhūti-Dvādaśī Vow: Pushkara
जन्मप्रभृति पापिष्ठौ कुकर्माणौ दृढव्रते तत्प्रसङ्गात्तयोर्मध्ये धर्मलेशस्तु ते ऽनघ //
janmaprabhṛti pāpiṣṭhau kukarmāṇau dṛḍhavrate tatprasaṅgāttayormadhye dharmaleśastu te 'nagha //
From birth they were thoroughly wicked, steadfast in evil deeds; yet, O sinless one, through their very entanglement with one another, between those two there arose at least a tiny remnant of dharma.
This verse does not discuss Pralaya directly; it focuses on moral causality—how even among the deeply sinful, circumstances and association can still produce a faint emergence of dharma.
It highlights a key Rajadharma/householder principle: association (saṅga) powerfully shapes conduct. A king should regulate courtly company and counsel, and a householder should avoid corrupting circles—yet also recognize that reform can begin from even a small ‘dharma-leśa’ and nurture it through discipline and right guidance.
No Vāstu or ritual procedure is stated here; the takeaway is ethical rather than architectural—dharma can appear as a small seed even in adverse moral environments.