CC Madhya 14.157
ataeva kṛṣṇera kare parama santoṣa
“There is no flaw or adulteration in the love of the gopīs; therefore they give Kṛṣṇa the highest pleasure.
Rasābhāsa occurs when one’s relationship with Kṛṣṇa is adulterated. There are different types of rasābhāsa — first class, second class and third class. The word rasa means “mellow,” and ābhāsa means “a shadow.” If one tastes one kind of mellow and something extra is imposed, that is uparasa. If something is derived from the original mellow, it is called anurasa. If something is appreciated that is far removed from the original mellow, it is called aparasa. Uparasa, anurasa and aparasa are, respectively, first-, second- and third-class rasābhāsas. As stated in the Bhakti-rasāmṛta-sindhu (4.9.1-2):
rasā eva rasābhāsā rasa-jñair anukīrtitāḥ
uttamā madhyamāḥ proktāḥ kaniṣṭhāś cety amī kramāt