My Elf Elder Sister

My Elf Elder Sister is an eroge visual novel, playing in the same world and time as the Taimanin games.

The main heroine is Sophia Arudisu Fairglyn is an Elf, which has been lving with the protagonist Kirihara Takuma and his father for some  years.

Summary
A world that is similar to the modern world. However, in this world, there are intelligent beings called "elves" who live in harmony with humans. How long have elves existed, and when did they evolve into something different from humans? Why were two intelligent life forms, elves and humans, born at the same time? The study to explore these mysteries is called "Elfology".

Kirihara Takuma's father, is a professor of Elfology at a university and a leading expert in the field. At their place, there is a female elf who lives with them. Her name is Sophia Arudisu Fairglyn.

Story
It took 200 years to find some very small villages of elves and only 70 years ago culture exchange took place. Though elves now can walk among humans it is a very rare sight simular to a celebrity. Both sides now hope to connect and understand each others better in this new age.

Kirihara Ryutaro, a researcher of elf studies, frequently interacts with elves in his university and studiesthe magic and origin of them. Takuma his son is a student in his university and Sophia (an elf) were childhood friends who played together since childhood. At the suggestion of Sophia's father, Sophia enrolls in Ryutaro's seminar as a special temporary lecturer and research sample in order to cooperate with the human side's research. Sophia's father suggested that she attend Ryutaro's seminar as a special temporary lecturer and research sample, and she went to the university every day. Sophia and Takuma had been like a sister and a brother, but as they grew older, their feelings changed.

Deep down, both Takuma and Sofia understand that they are becoming aware of each other as the opposite sex. However, because they were childhood friends, they were unable to take the next step in their relationship, and spent their lives under one roof.

Then one day, Ryutaro is away from home for a few days to present his research overseas. Left alone together, the two childhood friends, who are like an older sister and younger brother, confirm their feelings for each other and finally end up as lovers.

Takuma and Sophia are at the peak of their happiness. Takuma and Sofia are at the height of their happiness, but a fellow student Morino Fumiya tricks Sofia slowly into becoming his slave. In one of the endings she will used by him to gain new contracts into the criminal and political sphere.

Characters

 * Sophia Arudisu Fairglyn
 * Morino Fumiya
 * Kirihara Takuma
 * Kirihara Ryutaro

Trivia

 * The ending which used Sophia slave status for contacts, is referenced in Taimanin Asagi Battle Arena. It now has a follow up with her brought to the Chaos Arena, interacting with Orcs and Fumiya explaining about Igawa Asagi.