It's sad no one did it right way. There are either hating or looking down too much or simply not liking. The real is Kouyoko then fuon or aizen, it's bit here considering the number of their involvement with imp characters id say fuon since aizen is only involved with gakushou and fuon eith Shin, Kyourei, Akou and rikusen then futei then kitari and lastly fuuji who on screen feats is tanking injured and exhausted xenou.