I can already see it, 10-20 chapters for introduction, at least 20-30 chapter for each sister to interact with the mc, then ANOTHER 30+ chapter to be conflicted between them, then ANOTHER 10+ chapter for the other dude to give his opinion about it and the mc then go to discover his "true" feeling. Then he will choose NO ONE and continue live together while still have some kind of feeling for each other.
There you go, a 200 chapters manga.
There you go, a 200 chapters manga.