Imouto wa Shitteiru

妹は知っている / My Sister Knows / A Little Sister Knows At work, Miki Kiichirou is a dull office worker who is considered expressionless and boring. He stands out at drinking parties and doesn't seem to have any fun. But only I, his little sister, know that my big brother is actually "the most interesting in the world".
Alt Official Raw: Comic DAYS