18
Śrīmad-Bhāgavatam
[Canto 9, Ch. 18]
marriages are of two types, namely  anuloma  and  pratiloma .  Anuloma , marriage between a  brāhmaṇa  and the daughter of a  kṣatriya , is permissible, but  pratiloma , marriage between a  kṣatriya  and the daughter of a  brāhmaṇa , is not generally allowed. Therefore Mahārāja Parikṣit was curious about how Śukrācārya, a powerful  brāhmaṇa , could accept the principle of  pratiloma . Mahārāja Parikṣit was eager to know the cause for this uncommon marriage.
TEXTS 6-7
श्रीशुक उवाच
एकदा दानवेन्द्रस्य शर्मिष्ठा नाम कन्यका ।
सखीसहस्रसंयुक्ता गुरुपुत्र्या च भामिनी ॥ ६ ॥
देवयान्या पुरोधाने पुष्पितद्रुमसङ्कुले ।
व्यचरत् कलगीतालिनलिनीपुलिनेऽबला ॥ ७ ॥
śrī-śuka uvāca
ekadā dānavendrasya
śarmiṣṭhā nāma kanyakā
sakhī-sahasra-saṁyuktā
guru-putryā ca bhāminī
devayānyā purodyāne
puṣpita-druma-saṅkule
vyacarat kala-gītāli-
nalinī-puline 'balā
śrī-śukaḥ uvāca—Śrī Śukadeva Gosvāmī said; ekadā—once upon a time; dānava-indrasya—of Vṛṣaparvā; śarmiṣṭhā—Śarmiṣṭhā; nāma—by name; kanyakā—a daughter; sakhī-sahasra-saṁyuktā—accompanied by thousands of friends; guru-putryā—with the daughter of the guru, Śukrācārya; ca—also; bhāminī—very easily irritated; devayānyā—with Devayānī; pura-udyāne—within the palace garden; puṣpita—full of flowers; druma—with nice trees; saṅkule—congested; vyacarat—was walking; kala-gīta—with very sweet sounds; ali—with bumblebees; nalinī—with lotuses; puline—in such a garden; abalā—innocent.