Chambermaid

In this case, the "chamber" is a room within an alien spaceship, and the chambermaid prepares an alarmed Earth specimen for interstellar travel. The fluid in the strong bag confinement is a highly oxygenated liquid to allow for life - and better storage. So, no drowning here. The alien is of superior intelligence (note the considerable cephalization), sessile, and evolved much more from plants than animal. Quite a reversed role here, where we are the species that waters the plants!