The currency you have on hand is limited to what's listed in the mission kit and whatever characters make at their dayjobs - which likely isn't enough to rent an alien for a a vore performance, but hey there are ways to acquire things for trade or favors or something other than Shen. It would be totally possible to acquire, uh, such a resource but it would likely necessitate something more than just liquid assets for trade.

Below Shen, the most valuable resource on Waypoint Shril right now is access to ABA! competitors or arena seating, OR a way off the waypoint entirely. People are either looking to have the time of their lives on the Station or just trying to get the hell out of the way.

Tl;dr: It's totally doable, just get creative with how you pay for it.