Hanako Yamada

The Imouto is Senpai's little sister and a rival. She is a student at Akademi High.

Appearance
The Imouto will look like a gender swapped version of Senpai. Meaning that if Senpai is customized, she would have the same skin and hair color as him, but she will have a hairstyle that no other NPC will have. She will also wear special stockings to make herself stand out. If Senpai is kept at default appearance, then YandereDev said the Imouto would look something like this :

Senpai
She doesn't lust after her brother. She loves her onii-chan so much that she doesn't want him to get a girlfriend. She wants all his attention.

Trivia

 * Senpai's little sister was planned to at first be cute and innocent, but then later changed to be lewd and jailbaity.
 * If Senpai is a male, then she will still remain a female.
 * She is 2 years younger than Senpai.