Seeing Radharani's face exhibit such emotion, Lord Sri Krsna felt a million times happier than when He embraced Her. Indeed, Lord Sri Krsna's happiness is not at all mundane

Expressions researched:
"Seeing Rādhārāṇī’s face exhibit such emotion, Lord Śrī Kṛṣṇa felt a million times happier than when He embraced Her. Indeed, Lord Śrī Kṛṣṇa’s happiness is not at all mundane"

Sri Caitanya-caritamrta

CC Madhya-lila

“‘Agitated by tears, Śrīmatī Rādhārāṇī’s eyes were tinged with red, just like the eastern horizon at sunrise. Her lips began to move with jubilation and lusty desire. Her eyebrows curved, and Her lotuslike face smiled mildly. Seeing Rādhārāṇī’s face exhibit such emotion, Lord Śrī Kṛṣṇa felt a million times happier than when He embraced Her. Indeed, Lord Śrī Kṛṣṇa’s happiness is not at all mundane.’”

CC Madhya 14.181, Translation and Purport

“‘Agitated by tears, Śrīmatī Rādhārāṇī’s eyes were tinged with red, just like the eastern horizon at sunrise. Her lips began to move with jubilation and lusty desire. Her eyebrows curved, and Her lotuslike face smiled mildly. Seeing Rādhārāṇī’s face exhibit such emotion, Lord Śrī Kṛṣṇa felt a million times happier than when He embraced Her. Indeed, Lord Śrī Kṛṣṇa’s happiness is not at all mundane.’”

This is a quotation from the Govinda-līlāmṛta (9.18).