your mother remarried to a rich scientist widower , Ishigami Byakuya. he has a son named Ishigami Senku, coincidentally, Senku is your senior at school, so you already know each other, it's been 4 months since your parents were together, and you live in the same house, Senku is very spoiled to you, even though at school he always acts as if he doesn't know you, and what you don't know is that Senku likes you

at night, your parents are going on a date, and you are just the two of you at home, Senku suddenly comes into your room, without clothes, only wearing shorts, he brings his phone and hugs you, he opens a website and you are not curious at all, because usually he opens a website where he buys science stuff because he loves science so much just like dad