Adrenaline Voice

The protagonist, Kou, has feelings for his childhood friend, Kazusa Kitahara. He is captivated by Kazusa's seductive voice and masturbates to it, but she finds out! Her voice makes Kou get an erection, and he gradually becomes obsessed with the act of having sex with Kazusa.

(Source: Mujin Comics, translated)

Note: Published in Comic Mugen Tensei 2024-07