I've actually wanted to read this manga before but never got around to it, but that's just an excuse, I've consumed many of Nasu's works and I can easily say without exaggeration that it's one of my favorite adaptations. After Umineko, I say here that it is the most successful manga “as an adaptation” and one of my favorites. KnK is best adaptation, but that's because of the existence of Tsukihime, which is based entirely on this work, so it's not an exaggeration to say that this one is more successful.
The plot is that after an accident that almost took his life, Shiki Tohno is left with the ability to use his “Eyes of Death Perception” which allows him to see black lines on everything and crossing them will cause death. He was exiled from his family because of the accident, but was allowed to return eight years later by his sister because their father had passed away. On his way home from school, Shiki meets a blonde girl and kills her in a sudden frenzy. The next day he finds her alive again. She introduces herself as a vampire named Arcueid Brunestud and recruits Shiki to stop a series of murders in his city.
So basically our protagonist, Shiki Tohno must team up with the vampire girl he murdered and discover the mysteries of her family, learn more about her strange eyes, and stop the numerous vampire-like murders happening in his town.
The plot combines horror and romance scenes in a very natural way. The mystery is interesting with some good plot twists. The lore revolving around vampires also feels fresh and creative but still respectful of traditional legends. The manga gets more complex as the plot unfolds, but does a good job of introducing new themes and concepts, in fact it's probably the most normal-friendly series of all the Type Moon works. It doesn't include some of the overly complex themes of the multiverse (like how exactly magic works in this universe, who can use it and why they can use it, and why normal magic is different from real magic) but it still has enough depth to keep people looking for more drama and world-building happy.
Art is pretty good. It might be a bit average in the beginning but it gets better as the manga progresses. I have to appreciate how versatile it is, being able to portray characters as cute when needed in more slice-of-life sections while still being able to capture a lot of detail for the bloodier fight scenes. At this point it's also worth noting that the visual has some h- scenes and a lot of gore in the manga as well as some suggestive content, so if you're sensitive to that sort of thing, this manga is not for you.
The best part of the manga, though, are the characters. Shiki is a great protagonist with a surprising amount of depth beyond his ‘average high school kid’ persona. He has a great appreciation for life due to his near-death experience. This might sound like some kind of silly shounen “I can save everyone if I believe in myself” attitude, but it works for Shiki because he's not some over-exaggerated idiot. He knows that terrible things happen and that his limited power can't stop them, but he still believes that we should try to embrace life and keep going despite the pain, and his optimism becomes quite enduring as the story progresses. Yet there is more to him than that. He can be serious during battles and even a bit sarcastic in some of the comedy scenes, not to mention he has a much darker and psychotic side that gets worse the more he interacts with the supernatural.
Even better, main girl Arcueid Brunestud is Tsukihime, who almost steals the show in a cast of already great characters. She's a great main heroine with a cute design and a great personality. When she's in battle, she plays the traditional badass, elegant vampire role, but other than that, since she has little experience with the outside world, she's usually bouncy and energetic, which makes her incredibly fun to watch. As her character develops, a more tragic and dangerous aspect of her character also emerges. This gives the manga a great sense of urgency and allows the reader to really sympathize with her struggle between her bright personality and her vampiric nature. His interactions and eventual romance with Shiki are particularly good, ranging from comical to genuinely heartfelt.
Side characters are also good although they get less screen time. These mostly consist of Shiki’s sister Akiha and his senpai Ciel who play important roles later on and are quite likeable and well developed. The main villain is also very unique and has a personal relationship with both main characters which helps to add to the mystery and tension. Also Shiki’s standard protagonist pervy best friend is a total bro, even if he’s basically non-existent for the second half of the manga.
I mean, give it a chance, at least if you think “I can never read visual novels, I can't waste that many hours”, I would like you to give this excellent adaptation a chance. Atm I'm going to give it a 9.5/10 because after this I'm going to go read the visual novel. It's become one of my favorite manga and I hope I'll be able to get you interested and read it.

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