RPG MAKER GAMES:
1) You can try 'Cursed Armor'. It's pretty decent:
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2) You can also try 'Sword Princess Cistina':
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3) This one is good. 'Parallel Fantasy IF':
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4) 'Arms Devicer+' is also good:
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5) This one is old but it's considered a classic among Hentai Games.
'Virgin Island':
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I'm copy pasting this from a message I sent to another user a while back. All of the games below are Visual Novels, so no gameplay other than a few decisions that impact which ending and scene you get. All of them have the slow corruption you're looking for and very extreme sex.
VISUAL NOVELS
1) First, this is my favorite. If you're gonna play any visual novel I'm gonna recommend, then play this one. It's called Prison Battleship. You play as a type of terrorist/criminal older dude who is the captain of a space ship. One day, two beautiful female officers (who are very condescending to you and think you're scum) come to investigate you, and you slowly use some brainwashing equipment to turn them into "comfort" officers, AKA whores. It has a great story and lots of VERY extreme sex:
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2) The second one I'm gonna recommend is a direct sequel to the one above. Prison Battleship 2. You play as the same dude you played in the first game. This time, instead of officers, you brainwash two princesses (Very powerful women. Strong fighters, proud etc.) into becoming prostitutes. The story is great and I think you'll like it:
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3) The next game I'm gonna recommend is called 'Diviner Knight Towako'. This time, you play as Towako (Very proud. Strong warrior etc.), who is an heiress to a powerful family. She is a 'Diviner Knight' a powerful warrior/mage who kills demons. One day she gets captured by some Incubuses who slowly train her into becoming a prostitute. Good story and art.
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4) In the next game I'm gonna recommend, you play as a disgraced soldier who has been defeated/outranked by some beautiful Elf officers (both of which hate your guts). You escaped because of something bad you did and they come to investigate you, and using slow hypnosis, you slowly turn them into prostitutes. Again, good story and lots of perverted sex.
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5) Next game is called 'Armored Warrior Iris'. In this game you play as Iris, who is an armored warrior/knight. Basically Black Ops, elite soldier etc. One day, while on a mission, you are captured and sold into slavery and forced to become a prostitute. This game has a lot of choices and all of them will change the ending you can get.
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6) The last game I will recommend is called 'Space Pirate Sara'. In this game you play as Sara, who is a famous Space Pirate and an heiress to a powerful family. One day, as in all other previous games, she is captured while on a mission, by two, immortal, evil Loli girls and is slowly trained into becoming a prostitute, whore or their plaything, depending on your choices.
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