Seraph of the End, Vol. 31 (manga)

Yu and Mika continue to watch as long-lost, forbidden memories of the past unfold before their eyes. Paimon reveals the truth to Mikaela - that his existence is taboo and a threat to his father, Sika Madu. Distraught, the angel Mikaela takes matters into his own hands… Sika Madu watches as the perfect world made to reach the heavens crumbles around him and in a final desperate attempt, uses the Tower of Babel to enact the ultimate sin…