Is Obito still a human, or parasite or both, or weird stuff..

[narutoblitz]

No. His mind was slowly infested with Zetsu DNA until he went fully insane in Chapter 605 when he is shown saying ”なにをこれ、ああああいたい” which basically translates to "What is this? Ahhh!". When he used Mokuton it activated the same chakra received that Madara implanted into Nagato, which activated when Rinnegan was utilized properly the first time.

Black Zetsu contains Madara's will, so after death Madara manipulated the events of the manga. This is why Tobi had separate personalities. The real Obito "Tobi is a good boy" is still alive somewhere in there.