Harusaki Hinako

The protagonist's younger sister, the same age as him.

Always cheerful and full of energy, she quickly becomes friends with anyone.

She's no good at studying, but she has a keen sense for sound.

And so, despite originally wanting to be a voice actress, she's also good at composing music.

As the protagonist and his sister, she naturally ended up joining the PC gaming club.

She is attracted to the protagonist as a member of the opposite sex, and in fact often masturbates using him as a sexual aid...

Although she is very innocent, she likes erotic stories and has quite a bit of knowledge about them.