All it takes for evil to triumph is for Ennui to convince good men to do nothing.
The leader of the Seven Brave inhabits this arrogant weapon.
The deadliest Sinblade, Wrathbringer is coveted by the violent and feared by all.
In the Middle Ages, and even up to the early twentieth century, most of Europe's executioners were related: the Sansons and Deiblers in France, the Pierrepoints in England, etc. The reason for this was that, it generally not being socially acceptable to, well, kill people, executioners and their children could, generally, only marry other executioners or their children.
The parallels with massively inbred, Hapsburg-style dynasties are obvious- imagine a rather clever but politically inept satirist noting this, and being sentenced by the latter to a meeting with the former; even worse, imagine a dynasty of deranged and deformed executioners- think Texas Chaisaw Massacre with government funding.