These are the Vampires. They are not allowed to drink human blood on campus becaue there are humans on campus as well. There are hunting grounds on campus where vampires can catch animals.
Vampire anime guys with swords (sorry the pic. can't be seen. So instead this link will take you to the image.)
Hiro-Over 1000 years old. He has black hair and slightly red eyes. He is always carrying a the sword in the picture around, but Hiro will only use it to protect his life or someone else's. He is always a gentelmen and whenever he does something that makes him feel guilty he will lock himself in his room for days or years at a time. Hiro has no family because they were all killed by a beasts years ago and it sent him into a killing rage and he made those creatures extinct. Because of this he locked himself in his room for 100 years. Also he has a split personality, one is evil, dark and will kill anyone that gets in his way, and the other is the more dominate (the one described at the begining). Recently the evil one has come out more and more.