Ensures proper spore envelope assembly (PubMed:22463703, PubMed:26387458). Represses premature cortex assembly until coat assembly successfully initiates (PubMed:22463703). Also participates in a quality-control pathway that selectively removes defective sporulating cells through regulated cell death. Acts as an adaptator that delivers SpoIVA to the ClpXP proteolytic machinery for degradation, specifically in cells that improperly assemble the spore envelope (PubMed:26387458). Can form a complex with SpoIVA and ClpX. Localizes to the surface of the forespore early during sporulation, while coat assembly is initiating (PubMed:22463703). Localization is dependent on SpoIVA (PubMed:26387458). Proper localization may also depend directly or indirectly on the presence of SpoVM (PubMed:22463703). Expressed during sporulation and is regulated by the mother cell-specific transcription factors sigma E and SpoIIID. Deletion mutants produce heat-resistant spores more quickly than wild-type cells, but are sensitive to lysozyme. Overexpression causes defects in cortex maintenance and cell lysis.