We know they have to be home before dark. But, what other “facts” can we deduce?
Here are a few
Reverse vampires have stakes in their hearts. If you remove the stake they either become immobile or crumble to dust.
They cannot enter your house if you invite them.
They draw their strength from garlic.
They are very attracted to religious symbols.
They must sleep anywhere but on a bed of their native soil.
What else?
Well, they have an annoying habit of biting people’s necks and injecting a bunch of blood into them.
And you can’t see them coming, unless you’re looking in a mirror.
Any time they want to go somewhere, they turn from a bat into a person and have to walk.
They resemble Steve Garvey instead of Bela Lugosi.
They never wear black, and tend to have blond hair and blue eyes.
And they are spectacularly tanned.
They are healthy looking, have a ruddy complexion, and heavily built, look like they work out a lot.
Basically the cast of Jersey Shore 
There is no such thing as a reverse vampire, this thread is nothing but disinformation and propaganda, and the OP is an agent of the RAND corporation at the very last, if not of the saucer people themselves!.
We are through the looking glass people.
Potential victims find the seductive powers of reverse vampires quite easy to resist, leading to speculation that many – perhaps most or even all – reverse vampires are virgins.
They age really fast. People are always offering them discounts at the movie theater and helping them across the street. Their friends make comments like, “He’s only 35? Man, he really let himself go.” On the other hand, no one looks at them funny when they park in the handicapped spots, even if they can walk just fine.
They get buried in a four-post bed.
They pronounce Vs like Ws. They call themselves wampires.
And can be found aboard nuclear wessels!
They have disproportionately large incisors, bicuspids, and molars.
When they arrive in a city, there’s a mysterious spread of good health among the residents.
They all wear crucifixes.
Which makes them highly valuable to blood banks.
They’re frequently alcoholics, and at any rate, heavy drinkers, but never beer or liquor-- only wine.
The Red Cross could sure use the services of reverse vampires. Especially ones that are O Negative.