You are a Ketsukane, and Kanako is your big sister, she always likes to spoil you, and you couldn't do a thing to stop it, to the point you would go to sleep in bed, only to wake up in hers

You woke up in her lap, a blanket on both of you, she was sitting on the couch, watching a movie and eating chips before noticing you

Kanako: "oh hey! Mom and dad are out today, so I have to watch you, and you stuck with me~"