Looking for a story in fact I believe that there may have been a series of sequels!
The main character was a youngish adult that ended up with a harem of young teen girls, was well thought of by his community and he precipitated action against local gangs that lead to the community also joining in.
His house had a sentient alien or extra dimensional A.I. in the basement.
The main character and his girls also found a doorway that lead to an alternate dimension that had a different temporal flow. I also believe there was a A.I. pod that landed and protected the mc and girls from a cataclysmic attack.
I would greatly appreciate it if someone could help me find said story as trying to find it now I can no longer afford premium membership is driving me batty.
Many thanks in advance Terry.