I think you have to understand a bit about Tezuka to really appreciate some of his works like Kirihito. A lot of people who've only thought of Tezuka as Astro Boy/Kimba are quite shocked at his more experimental stuff. A lot of his more mature stuff is a combination of his response to the geika movement as well as his own personal "dark period" of financial chaos.
Kirihito, as well as MW, Ayako, Human Metamorphosis and others explore the darker side of humanity, so you need to be ready going in...