Lennith

History
Lennith is of matrilineal lineage, and is the son of Drake's Aunt. His father is also a descendant from the Great Demon King's bloodline, but far removed.

After the Great Demon Lord's death, the direct descendant Drake was supposed to be the successor, but  Xirdish interfered. According to him, Lennith should succeed the throne, not Drake. His desire for revolution had no room for Drake, so he took the previous Great Demon Lord's advisor as his pawn, and "found" the Great Demon Lord's last will and testament. With  backing him, Lennith was able to defeat Drake's Army.