>>4445579Well, not sure if you're anime-only or not but if you knew Satsuki's personal reasons...
After hearing that Renako is spending time with Ajisai, Mai flies back home from Europe just to crash their date.
After Ajisai leave Mai pushes Renako down and starts trying to have her way. Only thing that stops it is Haruna opening the door and Renako slapping Mai.
Mai runs crying to Satsuki and is like "I know you like me, so I want you to to me what I did to Renako so I can feel what it's like to have someone I don't have feelings for force themselves on me.
Obviously Satsuki kicks her ass out, but still points Renako in the right direction to save Mai from making even more stupid decisions.
The fact Satsuki eventually forgives Mai shows she is actually pretty nice.