The manga started quite gruesomely, it was pretty cool with the demonic insane psyco sister owning the MC in every sense.

The only thing that did not make any sense at all is why the Gods reincarnated that psyco sister.

It doesn't meet any of the typical reason to reincarnate somebody to another world, if anything that psyco should have been sent to He** or reincarnated to an inferno world, instead of having her reincarnate in the same new world as the brother.

The manga is weak in that sense, and several chapters later, for the MC that's several years later, apparently the psyco sister that was killed yet again, seems to be coming back to haunt him as yet another reincarnation as ... spoiler... ;)

Anyways, if you can ignore the fact that this manga breaks so many rules of the isekai genre, the story itself is pretty good, following the new life of MC developing new friendships and living happily with his new family, until the demonic psyco sister comes back to haunt him again.

If anything the author should have hinted the sister is actually a Demon G**, with a weird lu** for little brothers, then the story would have made a little more sense than in its current form.