Little Sister's Helper
While trying to borrow a dictionary; Nana -the younger sister- catches his brother doing.... well; you should know by this being a +18 book. At first thing are very awkward between them, but suddenly the brother started asking favors as to "even things out".
Before long "borrowing a dictionary" became some sort of keyword for them.
"Original" doujinshi by the circle TAKANAEDOKO.
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