Why dont siblings ever get proper happy endings?

Why dont siblings ever get proper happy endings?
Is Japan afraid of the purest form of love?

Why he turn black in the bottom panel?

He's drawn with darker skin in that doujin for some reason

The purest form of love in Japan is a 20-hour shift in a nondescript office building, followed by a nomikai and showing up with a smashing hangover the next day.

Sounds like my life

You forgot going home and finding your wife with the pizza guy.

I cant even tell who thats supposed to be

its oreimo

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