UkyoKuonji2004
He died at the end of the last OVA if that was what you were talking about. And I'm not 100% sure of what he died of as well. I know it's a disease but that's pretty much it. I was thinking maybe a version of the plague
or an std...=Kaoru only got it because they made out but that doesn't explain the break out all over his body, does it. but I'm glad that isn't how it ended up in the manga. they lived happily ever after with there son.