A fake blood capsule is an excellent prop to use to curtial getting chewed out by your boss.

Suppose you've fallen weeks behind on filing your reports, and the boss gets wind of this and calls you into their office to chew you out.

Nobody likes getting chewed out.

So, the thing to do is to get a fake blood capsule and hide it in your mouth, between your gums and your lip, and then as the chewing-out escalates, like right when your boss has really worked themself into a lather (notice I didn't specify "himself" or "herself," as your boss could be either, or neither, or both at the same time), but anyway, as your boss has worked themselves up to the the really aggressive phase of the chewing-out process, you surreptitiously bite down on the fake blood capsule, and then simply allow the fake blood to begin dribbling out of your mouth, rolling down your chin or your cheek.

At this point your boss will stop ranting and probably ask, "are you bleeding?"

There are any number of ways you can play this, from stoically insisting that they continue with the beratement and you'll deal with the increasingly horrific bleeding later, to suddenly collapsing to the floor, screaming and grasping your throat. If you have a knife handy, the latter will probably lure your boss within striking range, but I am a pacifist and would not recommend stabbing your boss in the throat, no matter how clean the opening they may foolishly present as they attempt to tend to your feigned wound.

At this point I have no further advice to give because, fucking Christ on a crutch, man!! Look at the situation you've gotten yourself into, in the boss's office with fake blood just pouring out of your mouth, like some kind of lunatic!!

Go home. Get some rest.