I have lots of fave mangaka/artist/illustrator. But my most favorite is definitely
Takarai Rihito
Her art is really so lovely. I fell in love with it at first sight when I read Seven Days. It was so beautiful and I love how I can recognize her art style so easily. And it turns out not only her art is amazing but also her stories! Her first manga, Hana no Mizo Shiru, was truly beautiful also! My other favorites are:
Hagiwara Daisuke
His art is gorgeous. What made Horimiya much better is because of his lovely art!
Takashina Yuu
Another amazing artist! I fell in love with it too at first sight in Deadlock.
Mikanagi Touya
I admit the reason I read Karneval was because of the fascinating art. But art aside, woah! The story is also awesome! I came to love the story and characters as well!
Tateishi Ryo
I came to love her art because it reminds me alot of Takashina Yuu-sensei's art style.
Yuzuya Haruhi
It's so cute! I really love her art! It's such a shame cause she only has really few works like Boku no Ano Ko, and this oneshot, Unexpected Love. I would love to see more of her works someday.
Tagura Tohru
I just really like the simpleness touch of her art. It has such a very sweet feeling that will make you smile when you see it. Especially in Haikei, Niisan-sama.
Abe Miyuki
From Komatta Toki ni wa Hoshi ni Kike! to Hakkenden and Super Lovers.. Abe Miyuki-sensei is definitely one of my most fave BL/Yaoi mangaka! Yeah at first her art in Komatta is kinda off compared to Super Lovers but come on! That was published around 90's! And It did improve alot in later chapters.
Art aside.. I also love her stories!
Sugiura Shiho
Just like Abe Miyuki-sensei.. her art at first wasn't that appealing like in Koori no Mamono no Monogatari but in later volumes... woah! It improved so much like wtf. And now in Silver Diamond.. it's really beautiful! Both in art and story!
Odagiri Hotaru
Another one of my super fave artists! I fell in love with it (again) in Only The Ring Finger Knows. But I'm happy that she made her own manga, which is Uraboku and the story is amazing too!
Yura
Her art in Lucky Dog 1 was really cute and nice but since LD1 was released around 2009, I think her art now has improved a lot more.
Ahh I really want to put more but it will never end! Some of my faves are (especially stories and mostly BL/Yaoi) are Konohara Narise, Junko, Natsume Isaku, Yamamoto Kotetsuko, Yoneda Kou, Nekota Yonezou, Ike Reibun, Hayakawa Nojiko, and many more omg