A stalker in the home... until he impregnates his sister whose breasts have started to swell.

A brother and sister with a slight age gap.
They live together under the same roof, but ever since the sister's breasts started to swell, he has been following her with his eyes.
My sister is completely careless and shows her panties as she wanders around naked after a bath...
As I watched her, I couldn't help it... This is a game where I end up impregnating her.
[Game background]
I have a sister.
Unlike me, she has always been popular at school.
Because we are brother and sister, I had never paid much attention to her before, but when I glanced at her as she was watching TV, I saw her budding breasts...
Since then, in the midst of puberty, I have been excited by my sister's sexuality.

There are no enemies that appear and I fight.
There are no adventures or treasure hunts.
I spend my everyday life as usual, and there is only my sister who lives with me.
As I pass through the living room to run some errands, I see my sister's panties, careless as she is relaxing on the sofa.
When I came back to the living room after finishing my errands, I found my sister's underwear trying to take off her socks.
When I was invited to dinner and tried to sit at the kitchen table, my sister was sitting on a chair with her legs crossed, wearing her underwear.
Wherever I went in the house, no matter what I did, I was wearing my sister's underwear (sweat)