Ojikatsu no Susume is a boy's love manga. In the story, new pets, ojisan (middle-age men), were invented. Ojisans are fed by human adult males sperms, which makes it legal to pop one's cock in public (wow), and feed the pets.
You can view this manga (sorry, Japanese only) here.
I would personally prefer a world with no woman, whether popping cock out in public and feeding pets are legally accepted. This story minus women, plus the option of transforming into an ojisan would be ideal for me.
