Another day, another time-stop/hypnosis story pulled out of upload purgatory. This doujin by the group rbooks was released in May/June 2019 and serves as a follow-up to another doujin released in February/March 2018. It's not immediately apparent that this is technically a sequel, but you do have cameos of two girls from part one on page 9. Just as runningnooblet succinctly put it years ago, the protagonist fuses with the school he works at and turns it into his personal domain.
Also, is this school connected to a bakery because my man is CAKED UP back there on page 25.