Onani Master Kurosawa
Also known as Fap Note

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Simple Description: Death Note + school life + fapping

The story is a narration of Kurosawa, who has a habit of masturbating in a Girl's bathroom. Hilarity ensues as his secret is exposed.
While there are no H-scenes (and exceedingly few ecchi scenes) it's still rated as for mature audiences (for obvious reasons).

All 31 chapters have been scanlated.