Pretty easy once I realized you could vote from two in each group.
ARENA 01: Ciel Phantomhive Death the Kid
[Lelouch Lamperouge] Sugisaki Ken Okita Sōji
[Kōgami Shinya]
ARENA 02: Oz Vessalius
[Diarmuid Ua Duibhne] Yatogami Kurō
[Kinoshita Hideyoshi] Watanuki Banri Tōyama Kinji
ARENA 03: Uchiha Itachi Sinbad
[Sakai Yūji] Sakata Gintoki Tsukiyomi Ikuto
[Kazehaya Shōta]
ARENA 04: Kujō Kazuya Hiraga Saito
[Kuchiki Byakuya] Li Syaoran
[Katsuragi Keima] Kurosawa Yamato
ARENA 05: Aladdin Uzumaki Naruto
[Kyon] Natsume Takashi
[Yagami Light] Kida Masaomi
ARENA 06:
[Iskandar] Monkey D. Luffy Hijikata Toshirō Okabe Rintarō Orihara Izaya
[Fukube Satoshi]
ARENA 07: Alibaba Saluja
[Edward Elric] Natsu Dragneel Okumura Rin Miketsukami Sōshi Hei
ARENA 08: Alphonse Elric
[Gilgamesh] Yoshii Akihisa
[Okazaki Tomoya] Akise Aru Akashi Seijūrō
ARENA 09:
[Waver Velvet] Accelerator Rokudō Mukuro Togashi Yūta Usui Takumi Kōsaka Kyōsuke
ARENA 10: Gray Fullbuster Yoshida Haru Ōma Shū
[Sakakibara Kōichi] [Araragi Koyomi] Kise Ryōta
ARENA 11: Satō Jun
[Natsume Kyōsuke] Okita Sōgo Aikawa Ayumu Emiya Kiritsugu
[Otonashi Yuzuru]
ARENA 12: Gilbert Nightray Hatake Kakashi
[Hinata Hideki] [Naoe Riki] Ayasaki Hayate Kuroko Tetsuya
ARENA 13: Roy Mustang Kamijō Tōma
[Koizumi Itsuki] Tomoe
[Sunohara Yōhei] Kotomine Kirei
ARENA 14:
[Archer] Gin Fuwa Mahiro Otonashi Io Takasu Ryūji
[Kurosaki Ichigo]
ARENA 15: Heiwajima Shizuo Kirigaya Kazuto
[Kanda Sorata] Hasegawa Kodaka Echizen Ryoma Hibari Kyōya
ARENA 16: L Lawliet Sebastian Michaelis Yagami Taichi
[Maeda Atsuhiro (Wien)] [Oreki Hōtarō] Sawada Tsunayoshi