Hi,

It's not parallel paradise. The beginning is a bit hazy but I remember that the MC dies and when he comes back he is in the other world where men have become these sex fiends, kicker is that he had died already in this parallel world and thus shouldn't exist.

He has a friend who had died in his original world who he loved and thus made the resolve to go to her and protect her. They are school students.

So he sets out on a quest and a few girls follow along. A few classmates and the teacher. As they go along one of the girls brings along her "Shota" brother who is also cursed with the lust disease and she wants to find a cure.

They eventually land upon a house where a grandma and girl are living and the grandpa and dad are locked away in a outside barn house. They shelter the girls for a while and then the MC leaves and a few girls follow and a few stay after one of the classmate girls kills the grandfather and dad.

There exists these crazy commando chicks who hunt down the rapist men and use them to pleaseure themselves with them but crave something real or unethical aka the MC or Shota.

I could provide more context than this but it's all a weird jumble of memories

UPDATE! FOUND!
https://www.mangaupdates.com/series/37vdez2/kyosei-tensei