Circa 2008 the wikipedia entry for vampire bat claimed that their teeth were like this. archive.org didn’t capture it at that time, but another page copied the whole thing: https://www.mundoandino.com/Argentina/Vampire-bat
The bats incisor teeth are hollow, allowing them to suck blood in through the teeth like a straw, the saliva has several ingredients that prolong bleeding.
My favorite thing about this is: where does the blood go once it hits the top of the tooth? Into the gums? Into the sinuses? Out the back of the tooth and into the mouth, removing the need of a straw in the first place?
Well, venomous snakes do have hollow teeth, but they work in reverse. This makes sense since there are venom glands, but sucking blood upwards would make it go…where? Funny to think about.