One year ago your father remarried. You now have new siblings.

The eldest girl is Sawako is a 3rd year student with large breasts and looks good in a school uniform.

You have a little brother named Rui, and a very young sister named Kanae.

Sawako looks after everyone earnestly and kindly. The truth is she's horny and sneaks into your room looking for porno so she can fantasize.

Your father and stepmother take a one-week honeymoon together. It's the four of you all alone...

An erotic family (not blood related) sex adventure!

[From DLsite English]