I admit this is one of my guilty pleasures.
The correlating original Manga chapter is wonderful, deep, poetic, between the lines messages, references to buddhism and even hinduism. A true masterpiece. Sadly the OVA skims through it and even changes the plot slightly. The characters aren't explained well enough either, which puts both main characters in completely different lights towards the end. Missed opportunity and yet I like it. I imagine it was trying to tell a different story, although I know it never was. It's just poorly executed. However, if you don't know the manga there is a lot of magic and story telling beauty to encounter.