As Nova pushed out on the walls, she'd find more give to them than she'd expect - The snake isn't keen on stifling her prey, at least not straightaway, and she'll have a few moments of (relatively) free movement before the walls gently close in on her, massaging and kneading into her body from all sides as acid begins to pour in, the normally painful sensation making pleasure tingle across her skin, and the tender massaging amplified in its pleasantness by a fairly great degree. As it went on, however, it would become harder and herder to move of course, and her body would slowly begin to break down within the snake. Until she felt nothing, however, all she'd be able to feel was pleasent sensations, the poor girl at least doomed to a pleasant, if temporary demise.