Random scenario inspired by the succubus talk in the thread. You're a researcher working in a lab, and a group of armed men are coming in to seize the research and gun down anyone whose working on the project. However, they have not yet been made aware of your presence. In front of you are two vials, the first one will turn you into a young, attractive girl. If they find you in this form, they'll assume you're an escaping test subject and will follow orders to take you in alive. This may make it easier to survive escaping since they won't shoot you and will only detain you. Even so, from the footage you've seen of them thus far though, these men are not of strong moral character, and you would not put it past any of them to try to take advantage of the chaos to rape you. On the other hand, if you take this vial in conjunction with the second highly experimental vial, this will turn you into a succubus, complete with their powers of charming, unmatched strength, and ability to hide their monster features, but also their insatiable lust for the male essence. There is absolutely nothing these men can do to you, but you will also have to fight your own urge to rape and consume their life force sexually instead. Theory states, that this urge upon seeing a male fresh after transformation is the equivalent of having not eaten in two days and seeing your favorite meal in front of you, with it growing with each passing hour, even though you won't die if you don't satisfy that urge.
It may be possible to turn back to normal from either of these things, albeit an unwarranted pregnancy is unexplored territory and would complicate things. Furthermore, the orgasm of a succubus is such a powerful feeling, research hypothesizes nearly no human would be able to muster the willpower to want to turn back.
What actions would you take in this situation? Not taking either vial and trying to sneak out or trying to use it on someone else are also fair game.