Now...
My other issue is this.
Diet: These creatures enjoy the taste of meat and marrow to supplement their feeding, but they require large amounts of blood to sustain themselves. It is blood that they hunt for, and blood that they crave. This biological need more than anything dictates the small size of their social groups. Though their slow metabolism gives them the ability to go for a week or sometimes two without feeding, they must still eat regularly. Even the endless expanse of the wildlands would be unable to supply enough blood for these creatures to congregate in large numbers.
When feeding the Aroike typically puncture an artery and drink whatever blood they can suck from the victim. Once no more blood is available they tear free fat, muscle, and bone to chew. Upon draining the remaining scraps of their fluid they crack the bones, eat the marrow, and leave the remains on the ground for scavengers.
This is a big creature. Just looking at it tells me blood won't do the trick. It seems cliche and too 'its a mutated bat monkey thing!' for my tastes. Can we ditch the blood thing and actually have it eat a wide variety of foods - human meat perfectly acceptable and a large chunk of their diet included? Really... if you're light as a feather and have incredibly thin bones and weigh almost nothing like a bat does, then blood makes sense. Even high protein makes sense. But this fellow is gonna need some fruits and veggies too.