Oni is part of the Second Season, it basically goes Neko (White) - Kabuki - Otori - Oni - Koi with Hana floating around separately due to missed deadlines.
Owari is pretty good, if you like Senjougahara, you would really enjoy Hitagi Rendezvous arc. And she also has short but cool appearances in other arcs too.
Manga is good, but I disliked its ending.