This article may refer to two different members of the Seyfarth family, who have been known to wield the Demon Sword Grollschwert and the Devil Scythe Grassense throughout the generations:
- Raimund Seyfarth, the legendary war hero who wielded Grollschwert and Grassense and was known as Thanatos in his living days before his death four years prior to Rosenkreuzstilette.
- Grolla Seyfarth, the current heiress to Grollschwert; she is the granddaughter and former apprentice of Sir Raimund.