Why isn't Strip Poker for Windows listed here? You have Valkyrie Hentai Anime Poker but not that.

Strip Poker for Windows wasn't created in Japan. We're aware of its existence, but this site is focused only on games originating out of Japan. Valkyrie Hentai Anime Poker was however created by JAST (as the page for it states, its original title was JAST Poker) and translated by JAST USA for the stateside release. JAST USA has a history of changing a few titles in their USA releases, e.g. "Knights of Xentar" from Dragon Knight 3.