So rakan's plan was to "have sex with her" / "take her virginity" and in doing so, lower her value in the eyes of the guys pinning for her (since she didn't sell her body (at all, I think. I could be wrong)).
What he didn't anticipate though, was her getting pregnant. Usually this doesn't happen when courtesans sleep with their guests, since they take drugs beforehand (so they don't get preggo). What happened was the courtesan intentionally didn't take the drug, in order to get pregnant, in doing so, making the two guys gunning for her lose interest, her price falling, and then rakan being able to redeem her. But stuff happened and as you can tell from this chapter, things obviously didn't go according to plan.