Kamasutra 5.6.4

5.6.4

rājānaś ca kṛpāśīlā vināpi bhāvayogād āyojitāpadravyā yāvad artham ekayā rātryā bahvībhir api gacchanti/ yasyāṃ tu prītir vāsaka ṛtuv vā tatrābhiprāyataḥ pravartanta iti prācyopacārāḥ//

Some Kings, who are compassionate, take or apply certain medicines to enable them to enjoy many wives in one night, simply for the purpose of satisfying the desire of their women, though they perhaps have no desire of their own. Others enjoy with great affection only those wives that they particularly like, while others only take them, according as the turn of each wife arrives, in due course. Such are the ways of enjoyment prevalent in Eastern countries, and what is said about the means of enjoyment of the females is also applicable to the males.