Looks like it could lead up to some decent brother-sister romance. Unfortunately and depressingly, this seems to have a narrative and theme that allows the now apparent cuckoldry-bait (especially in the last few chapters with the obnoxious clingy bishie freak) and hamfisted societal drama to...
It's refreshing to read incest manga that actually delivers and isn't cop-out NBR trash, NTRbait or some contrived harem setup where the MC ends up with some random woman instead.