User blog comment:B214/High School DxD DX.4 discussion/@comment-30924344-20170704000014/@comment-2A02:8109:10BF:B444:649C:85C5:6D54:DA2C-20170710011822

Could be also Sakrà! Juts because he already appeared doesn`t mean he is not the final Boss. I don`t think that kartikeya, Shiva`s son would do anything to Issei. Will even see Issei as a little Brother.