Ah, how I love 4chan's /a/ population and its obsession with sisters. Mostly younger sisters (imouto in Japanese), but some have a thing for older sisters (onee-san/chan/sama). Either way, 4chan's /a/ board is a cesspool of incest-love.
As someone with a little sister myself, I can't help but shake my head and laugh. To be fair, anime in recent years have promoted this more and more. I remember being shocked by Kanako's character from Love Hina back in the day. Now her character is a typical archetype in most harem shows, sometimes even the main heroine, as was in the case of Da Capo and Da Capo Second Season (I still have no idea how I sat through 2 26 episode seasons of that - I would take it back if I could). And I don't see the trend slowing down.
Anyway, the reason I made this post is because I found a particularly hilarious post on /a/ today and thought I'd share. Regardless of whether or not it's based on reality (I doubt it is), this guy needs to keep writing.