Tonari no Onee-san wa Osewazuki

I love caring older sisters! That older sister who always played with me started fussing over me again. Conscious of her body transformed into an attractive woman, the protagonist couldn't help but get hard and asked her to jerk him off. Things just flowed from there into sex!

(Source: Mujin Comics, translated)

Note: Published in Comic Mugen Tensei 2023-01