Matthew is old as heck

Obviously, this comes with being a vampire but it needed to be said. Edward is about 116 years old in and appears to be 17 while Matthew is over 1,500 years old and passing as a convincing 37 years old. One of the best parts of the book, that sets it far apart from Twilight, is that it goes deep into his past.

Diana has a vision of his past and it gives us a deeper insight into who he was. Having his mother Ysabeau share stories that she knew and also the little trinkets that he has sprinkled throughout his life helped build a better story than the one we ever got from Stephanie Meyer, though.

Diana and Matthew are engaged (literally) in a very dangerous relationship

In A Discovery of Witches, Matthew is drawn to Diana who is a witch; it is later revealed that their relationship is a bit riskier than Edward and Bella's and basically leads them on a wildly dangerous adventure while fighting to keep their relationship alive.

One of the most scream-worthy parts of the first book was when Matthew finally revealed how he felt about Diana despite the challenges that they faced from the Congregation (the Congregation is what we will compare to the Voultori).

He is a protective man

Bella gives in to Edwards demands and protective side rather easily which can be hard to watch for some because we want a strong female lead. In the case of Diana, though, she is strong and will give in only to Matthew's protective side and throwing back major sass when he tries to command her later in the series.

Matthew sees it as his job to protect Diana from others of all kinds (daemons, vampires, and witches alike). Without the use of her powers fully in her control, Matthew sees it as an even bigger responsibility to keep her safe.

He lives a "vegetarian" lifestyle but used to prey on criminals

Matthew and his family prefer to drink the blood of animals rather than the blood of humans, much like the Cullen's and their strict 'vegetarian' ways. In one of the later Twilight books, it is revealed that Edward would hunt criminals and use them as his blood source instead of innocent humans or Bella. In the same aspect, it is told to Diana that he would do the same thing if he had to drink from a human.

Matthew refuses to turn Diana

Unlike Bella, Diana is not whining and begging to become a vampire. She is (for lack of a better phrase) happy with being a witch. One nice thing about these books is that they do not harbor on the fact that he is a vampire and she is not every other page. Matthew and Diana rely on her powers so much that it wouldn't be smart to turn her anyways, but Matthew has stated once or twice that he will not change her and that is that.