Delirium says:
... If she is not willing to suck the blood out of the tube ...
Sorry that I was not clear. She is lapping up the blood as fast as it comes out, but she is a vampire so she wants to bite what she eats so she is chewing on the tube and the blood-covered door.
Sucking on the tube could cause the vessels to collapse, so it is better this way, as Bev would point out. :)
What you are doing
is working, you just have to keep it under control long enough for Chablis to get enough blood in her to calm down a bit. But the act of feeding is not a calm thing, even
Benji might do you 3-Harm when he feeds (and that would kill someone like Bev), so there is a clear lack of control in the act.
You will need to impose that control.
Delirium says:
... it appears she is not cooperating? ...
Not
passively cooperating. It is taking too long.
Delirium says:
... Emma isn't going to let Chablis bite her. ...
Absolutely.
Emma's instincts have proved correct every step of the way. Not to hurt the vampire because it is Chablis, to use fresh blood not the bagged stuff Bev brought, to not allow a bite, and so on.
If
Emma keeps trusting her instincts she may be able to pull this off.
At its most essential you could
Keep Your Cool to avoid losing control, but that is a base-case and you probably have better tools at your disposal.
Maybe you use the threat of taking away the blood to
Persuade her to behave? Maybe you threaten her with the return of the scary demon lady?
Persuade would require your getting through to her, though. Maybe your words are persuasive enough? Or maybe
Persephone needs to get her game-face on and pin Chablis down for the duration? (poor Bev)
Options abound.
Whatever you do, we will probably need to talk about
Sharing a Moment of Intimacy between
everyone or some subset of everyone here.