The Tsuguko (継子,lit. successor?) are exceptional members of the Demon Slayer Corps who are personally designated as the successors of the Pillars, particularly to take their place when they die or retire.
Demon Slayers can become a Tsuguko either by applying and getting accepted, or by being scouted personally by the Pillars themselves. A Tsuguko normally uses the same Breath Style as the Pillar, though this isn't a strict requirement.[1]
