Emo Little Brother Steals His Breezy Big Sister

Story :  Our protagonist, Iori, has a boyfriend who's kind and cool.
But the sex... Well, it leaves something to be desired. This is why Iori's relationships with men never last.
It's not that she's frigid... It's just that using sex toys is far more exciting than sex
And above all, it feels way better!

One day, while indulging in her usual solo play, her nerdy and socially inept younger brother, Aoi, knocks on her door.

The gloomy boy has an unexpected request for her:

"My girlfriend doesn't seem to enjoy sex with me."
"What can I do to please a woman?"

Iori decides to be a good older sister and agree to help him on a whim. However...