I mean, you can get with Noriko and Yasuka in all 3 non-reject routes so I'm not sure what would be complicated by it.
Love route: She absolutely refuses to take away her daughter's love. The one path you can not get Sayuri on.
Corruption route: Sayuri resists the urge, but if you have sex with Asami at her house while Sayuri is home it will break down that wall. At first, you can only do anything when you visit her at work or while Asami is at the park. But Asami eventually sees the two of you (probably from help of a certain stalker) but instead of getting mad she suggest you please them both.
Friendship/reject: Keep as is (which I have no idea what it is as I can't get to that part due to current bugs!!!)
Future ideas:
Noriko x Yasuka (Blackmail x Corruption) 3P - Yasuka finds out about the blackmail but considers it an appropriate punishment for how she use to treat him and joins in.
Noriko x Yasuka (Fem/Maledom x Love) 3P- The two knows for a fact you're banging the other and decide to stop pretending not to notice. Slight difference depending on Noriko's route.
Noriko x Asami (Maledom x Love) 3P - The two have become friends and shared about their intimate moments with MC. So one day when you invite Asami over, Noriko knocks on the door.
Noriko x Asami (Femdom x Corruption) 3P - Similar to above but at the park or Asami's home. They combine to fulfill some of their fantasies, at the cost of the MC...
Noriko x Asami (Both Reject) Yuri - Two people licking each other wounds, literally.
Yasuka x Sayuri 3P - Mothers getting closer.
Noriko x Asami x Sakura (Fem/Maledom x Love/Corrupt) Yuri - Revenge time.
Noriko x Asami x Sakura (Maledom x Love) 4P - Because it's currently Thursday.