Battle: King's Landing

(Date A Live fan fiction) A man with no past, a long blade with a strange shape, a product of an elf in front of him, a boy named Itsuka Shidou, a strange church built by humans and the justice organization of AST. When the malice that fills every corner of the world is concentrated on one person, will that sharp blade cut through the sky again, and who will reveal the lost past? (It's not a cool novel, the changes are quite large, but the only change is that people spontaneously form a church that longs for redemption. The protagonist may not be as good as you think, and the plot is not very good. The protagonist is quite realistic, so be careful.)