Kamasutra 6.5.14

6.5.14

tatrāpy ātyayikato viśeṣaḥ/

When there are two lovers, one of whom is generous, and the other ready to do any service for the courtezan, some Sages say that the one who is ready to do the service should be preferred, but Vatsyayana is of opinion that a man who does a service thinks that he has gained his object when he has done something once, but a generous man does not care for what he has given before. Even here the choice should be guided by the likelihood of the future good to be derived from her union with either of them.