Kamasutra 2.9.7

2.9.7

saṃvāhane pariṣvajamāneva gātrair ūrūnāyakasya mṛdgīyāt/

Eunuchs disguised as males keep their desires secret, and when they wish to do anything they lead the life of shampooers. Under the pretence of shampooing, an eunuch of this kind embraces and draws towards himself the thighs of the man whom he is shampooing, and after this he touches the joints of his thighs and his jaghana or central portions of his body. Then, if he finds the lingam of the man erect, he presses it with his hands, and chaffs him for getting into that state. If after this, and after knowing his intention, the man does not tell the eunuch to proceed, then the latter does it of his own accord and begins the congress. If, however, he is ordered by the man to do it, then he disputes with him, and only consents at last with difficulty.