Sims especially have very little tact when it comes to these matters, which is again where it comes in handy to be able to impose your will over them.
And drinking blood from the bar and eating blood fruit salad was a way I satisfied their hunger occasionally, prior to trying your mod.
This is going to enable cheats and if it works it will say cheats are enabled.
It always goes back down to a yellow bar and that they need blood or they smell blood when they are already drinking it.
The woohoo lover custom trait is a great option if you have a sim who absolutely loves to participate in the art of woohoo.