https://www.dlsite.com/maniax/work/=/product_id/RJ01405294.html
https://www.melonbooks.co.jp/detail/detail.php?product_id=3056942

[Synopsis]

There was a younger brother who had always felt inferior to his older brother who was both good looking and smart.
However, one day, his older brother suddenly contracted a disease that turned him into a woman and their relationship began to change.
After he turned into a woman, his older brother began to show his mentally weak side and depend on him and the younger brother began to find him cute and lovable.
Eventually, the younger brother fell in love with his older brother and he lost all reason and forced his refusing older brother to experience the pleasure of being a woman...!
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¯|_(ツ)_/¯

Base +28, RagNaRog +7, Sylvrwolflol +8, Fofotron +26

Prety good vanilla ts, like the artstyle.

Base +6, liberius +6