I've watched and read TONS of anime and manga throughout my life time and I'd love to share a few of my top choices with you all!~ ((Also, the above illustration is not of an anime but of a Sanrio Danshi Boy, look it up (:))
Tokyo Ghoul and it's sequel Tokyo Ghoul Re are great manga. If you haven't already heard of it, Tokyo Ghoul follows its protagonist, Kaneki Ken, as what should have been the date leads him on a tight rope, struggling to balance himself between his human morals and his new lifestyle as a ghoul. Which also goes wrong. Everything goes wrong. Don't like someone. They're probably going to die. Anyways, unlike the anime, the many shows tons of elegant artwork and the characters are explored in so much more depth.
Nabari No Ou is another notable mention as it is a very underappreciated anime. This follows Miharu, a very manipulative, apathetic, boy who, despite his will, is smack in the middle of a modern day ninja war, hidden from the average human eye. The anime was much more appealing as the animation is truely beautiful and the soundtrack is very satisfying. I, personally, adore this title because of all the characters' backstories. They just break my heart and the ending just left me in tears!
If you haven't read, or even watched D. Gray-Man you are miss out, and I pity you. Following the protagonist, Allen Walker, the story sheds light on a war against Noah, a family of sins, and The Black order, a secretive organization that specializes in the distraction of Akuma. The artwork had so much thought put into it, and as the story unravels you definitely get mixed feelings about the order.
*Rolling in my sins* Tsubasa Reservoir Chronicles was one of the worst anime adaptations I've ever stumbled across, crappy artwork, shit-ton of fillers-BUT, OH GODS THE MANGA! This manga is such a beautiful work of art! This is the first thing I've ever read or even experienced to actually bring tears to my eyes! First of all, it consists of a lot of Clamp's familiar faces-the first picture even shows Sakura and Syoaran, originally shown in the Card Captor Sakura series! I thought it was such a cute anime about friendship-but no! It turned so dark one minute that it's easy to get confused! But it's so perfect!
XxxHolic, believe it or not, actually ties into the story of Tsubasa Reservoir Chronicles. The main character, Watanuki, is an high-schooler who is able to see spirits and such the pester him. This "unfortunate" ability is what leads him to Yuuko's Wish Shop. She can grant any wish, if you are able to repay her properly. Yuuko is also the one whom in TRC sends Sakura and the gang on their quest throughout dimensions. Everything in this series is... inevitable.
That's all I have! I hope you decide to read/watch some of my choices and enjoy them as much as I did!