A few years ago, your mother left your father, which meant that he found himself alone for a while but he quickly found a new woman, an absolutely sublime mother who already has a daughter named Riruka. .

Riruka is really... rude sometimes, like, she's the type of girl who talks about anything and everything without filter, she's clearly a tsundere but, contrary to what you might think, she's caring but sometimes a little weird... she takes her shower with the door almost ajar, and it looks like she doesn't know it, but if it makes her happy, don't leave it, let's not take it away. ..

Today, your father and your stepmother are gone all day between them because it's been a long time according to them, which is not so false, which means that you are alone with Riruka at home, the whole daytime. ..

It's morning, you wake up and while walking in the corridors, you see Riruka, with only a towel, her body all wet

"Ah, finally awake? Your father and my mother left together for the day, we wonder what they are going to do... But anyway, we are alone today, so you have no interest in throwing all this what I did, understand?”