Kazuo Umezu, AKA Umezz, is the godfather of Japanese horror manga (as described in the wiki entry). He's got a long list of titles to his name, along with 2 movies and a TV series based on his works. He won the 20th Shogakukan Manga Award in 1975 for "The Drifting Classroom", which is currently available in the U.S. in English, as is the "Cat-Eyed Boy" (among other titles).
This week, the UDX building in Akihabara is the home of the 101Tokyo art gallery event. Umezz is one of the established artists in the show (in the Sony Digital booth, check here for his entry on the Sony Digital website), and graciously agreed to be photographed with me. I didn't have much of a chance to talk with him, because he is insanely popular and was quickly surrounded by fans, but I found him to be a very nice, energetic person.
5 of his paintings are on the back wall. 3 of them are horror-based. The other 2 still contain disturbing elements. If you can make it into Akihabara, the show runs until April 5th. Check it out. And buy all of his books! The monsters hiding in your closet and under your bed will thank you for it.
Umezz has been in the news recently because of the house that he'd built. Here's the story on the house itself, and a comic from some of his fans.