@Tamerlane I mean why can't they use Sumire's divine craft not first arcana. In the last chapter Sumire's divine craft went past the 72 hour limit that the first arcana has, so why can't they just use her divine craft to go revert them back before they got infected?
So just last chapter they reveal that Sumire's divine craft can rewind time which is a better first arcana, but now they don't use it to cure everyone?