Kubja, also known as Trivakrā (crooked at three spots on her body), was a hunchback maidservant who desired Krishna. When Krishna visited her house one day, Kubja offered to apply ointment to His toes which Krishna agreed to. While applying the ointment, She smelled the fragrance of the Lord's feet which resulted in her being freed of her deformity and transformed into a beautiful woman. After the ointment was applied, the Lord felt extremely pleased by her act and granted her a boon. She begged the Lord to satisfy her carnal desires for Him to which Krishna promised to. Her story is mentioned in the Srimad Bhagavatam.
SB 10.48.1: Śukadeva Gosvāmī said: Next, after assimilating Uddhava’s report, Lord Kṛṣṇa, the Supreme Personality of Godhead, the omniscient Soul of all that be, desired to satisfy the serving girl Trivakrā, who was troubled by lust. Thus He went to her house.
SB 10.48.2: Trivakrā’s home was opulently appointed with expensive furnishings and replete with sensual accoutrements meant to inspire sexual desire. There were banners, rows of strung pearls, canopies, fine beds and sitting places, and also fragrant incense, oil lamps, flower garlands and aromatic sandalwood paste.
SB 10.48.3: When Trivakrā saw Him arriving at her house, she at once rose from her seat in a flurry. Coming forward graciously with her girlfriends, she respectfully greeted Lord Acyuta by offering Him an excellent seat and other articles of worship.
SB 10.48.4: Uddhava also received a seat of honor, since he was a saintly person, but he simply touched it and sat on the floor. Then Lord Kṛṣṇa, imitating the manners of human society, quickly made Himself comfortable on an opulent bed.
SB 10.48.5: Trivakrā prepared herself by bathing, anointing her body, and dressing in fine garments, by putting on jewelry, garlands and perfume, and also by chewing betel nut, drinking fragrant liquor, and so on. She then approached Lord Mādhava with shy, playful smiles and coquettish glances.
SB 10.48.6: Calling forward His beloved, who was anxious and shy at the prospect of this new contact, the Lord pulled her by her bangled hands onto the bed. Thus He enjoyed with that beautiful girl, whose only trace of piety was her having offered ointment to the Lord.
SB 10.48.7: Simply by smelling the fragrance of Kṛṣṇa’s lotus feet, Trivakrā cleansed away the burning lust Cupid had aroused in her breasts, chest and eyes. With her two arms she embraced between her breasts her lover, Śrī Kṛṣṇa, the personification of bliss, and thus she gave up her long-standing distress.
SB 10.48.8: Having thus gotten the hard-to-get Supreme Lord by the simple act of offering Him body ointment, unfortunate Trivakrā submitted to that Lord of freedom the following request.
SB 10.48.9: [Trivakrā said:] O beloved, please stay here with me for a few days more and enjoy. I cannot bear to give up Your association, O lotus-eyed one!
SB 10.48.10: Promising her the fulfillment of this lusty desire, considerate Kṛṣṇa, Lord of all beings, paid Trivakrā His respects and then returned with Uddhava to His own supremely opulent residence.