Sengoku Rance

I've bee playing this. It's a porn game although... with a story and you need actual brains to win at it. It's pretty damn cool and the main character is fucking hilarious... if a bit demented.

http://alicesoft.wikia.com/wiki/Sengoku_Rance

And no you do not need to play the other games to understand... not that you'll care. I learned about this on /v/ and was pleasantly surprised to see there was more to this game than just porn.