Well, D is the central figure in Vampire Hunter D graphic novels. He has this unique background that makes him both feared and respected. Then there's Rei - Ginsei, a vampire noble who is one of D's more formidable foes at times. There's also the Left Hand of D, which is a kind of sentient entity within D that gives him some special abilities and also provides some interesting internal dialogue. And let's not forget about the various villagers and townspeople that D encounters on his hunts. They often play a role in the story, either as victims or as sources of information.
The unique features? For one, the setting. It's usually in a post - apocalyptic world which gives a really interesting backdrop. The Vampire Hunter D graphic novels also have a great blend of horror and science - fiction elements. You've got vampires, which are the horror part, but then there are also advanced technologies that add the sci - fi touch. And D's character is complex. He's part vampire, part human, which makes his internal struggles and actions very engaging.
I'm not entirely sure as I haven't read it in detail. But generally, it might be about a vampire hunter named D and a character named Leila. It could involve their adventures in a world full of vampires, perhaps battles against the undead, and their own personal stories and growth within that dangerous environment.
For some readers, it could be a bit challenging as it has a unique world - building with its own set of rules regarding vampires, dhampirs (half - vampires like D), and the post - apocalyptic setting. However, if you take your time to understand these elements as you read, it becomes easier. The story also has a lot of action and adventure, which can help keep you engaged even if you are a bit confused at times.
Since it's part of the 'Vampire Hunter D' series, volume 7 novel would likely follow D's ongoing battle against vampires. It could explore more of D's past or his unique abilities. There might be new challenges for D, like a powerful vampire lord that he has to defeat. The story could also introduce new elements to the world - building, such as different types of vampire powers or new regions that D travels to. And it might also show how D's actions affect the relationship between humans and vampires in that world.