From Manga-Sketchbook:

Young Ko is about to learn a new hobby...

Ko Higaonna, sharing a moment with his not-quite-girlfriend Satomi, is disturbed to discover a sallow-faced man watching with infrared goggles from the darkness. Ko's sense of privacy is offended, and soon blood is spilled, and the goggles pass into new hands. But the Voyeur remains, and now Ko is his pupil, about to discover what goes on beneath the smiles on people's faces... What goes on in private, in the dark...?
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