Teased at the end of the Koibito ja... Nai. tankoubon release, and confirmed to be releasing after Koibito ja... Nai. 2: Ogasaka Tsubaki-hen.

My feelings will never be mutual… And this guy's lust is taking over her body and soul…
 
(Source: Coolmic)
 
Notes: 
- Published on web stores as Demo Hoka no Otoko no Yokubou wa Naka made Todoku...: Seto Karen-hen (でも他の男の欲望はナカまで届く…瀬戸花恋編). 
- Split into 15 episodes on mobile reading platforms. 
- Split into 12 episodes in long-strip format on Coolmic.

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