"Uu-?" summary: (chapter1: Looking at Koumakan - 1 of 5) A lot of Remiryas go toward Koumakan(Scarlet Devil Mansion). But, havitants of Koumakan don't need more Remiryas. So Sakuya made invisible Kekkai(Seal Barrier) around the Koumakan with the aid of Reimu. Remiryas bump against Kekkai. But they can't understand what there is.