The glossary of the novel explains this as follows:
The afterlife for the honored dead, where all true warriors go after they die to fight an eternal battle. The closest Klingon equivalent to heaven.
Cite this entry
Definition of {Suto'vo'qor}
from the Klingon Language Wiki:
https://klingon.wiki/Word/Suto-vo-kor
Retrieved 03 Feb 2023