"I won't compromise on this CP!"

I was reborn as the villainess in the R-rated game "Paradise of Angels and Demons" that I played in my past life. Seduce men? Unrequited love for my sister's boyfriend? No way, no way, I'm just a small-time villain, and I love my big sister!! My memories of my past life are hazy though. But I need to protect my big sister from the scenario using the game knowledge I do remember. My goal is to watch my sister and Rin's lovey-dovey scenes every day with a silly grin on my face. ——But why won't they start dating!? Th-this is strange. It should be about time they got together. Hmph, I'm working hard to make sure there are no obstacles like in the game. Huh? I hear something. Don't take action? Stay quiet? Stupid? ……I-I can't hear youuuu. Alright, today too for my sister's happiness, in this life plus extras I'm involving angels, demons, gods and all——wait, I'm getting involved? Well, I guess you could say that. Anyway, even though things are tough, let's do our best, yay! ………Oh, as long as I don't get involved, I'm harmless, right?