https://www.dlsite.com/maniax/work/=/product_id/RJ359622

No text: page 297

很好的结局，女主用身体作为武器反杀，既沉溺性欲，也保持了最初的目的，比起一般雌堕好得多，其实女主是自己选择沉溺性欲的而不是被调教出来的，这是最戳的地方，在后期性爱中，真诚和演技并存，更戳，其实也是同一模样。建议其他TS作品也学学。

Base +6, liszz +6, TAT21 +4, Youwin -8, JUSTH87 +6, Jackwuchn +3, 神渊之龙 +6, Kansaki01 +2, mayasama +6, bismarckdrei +6, pupss97162 +11, v228200 +6, Swind192672 +8, and 7 more...

这作者TS作品看上去都不错？

Base +5, 神渊之龙 +6, 小柯_小哀 +6, HYoules +3

So i MTL the summary using deepl and google translate, kind of inaccurate

Rei Himukai (MTL name) is a servant that was picked up by the family for unknown reason, he took over lady reika (blue eyes) in order to get revenge on his father who abandoned rei and his mother in extreme poverty.

before he can take over, rei father business takes a turn for the worst, the man who supported his father appeared putting condition for her support.

Will she lose everything and live with the debt, or will she marry the man?

'My father(revenge partner) bowed to me and asked me to marry him, and though I was reluctant to do so'

Rei reluctantly agrees to marry him

"I'm marrying into a family that's higher in rank than yours.

Thinking this is a chance to move up, she tries to take the initiative and ride the high horse, but...
She can't stand the pleasure of woman for the first time and have sex all she wants with a man.
And the man even trains her to become "his favorite woman"... In the end...

In order to get revenge and become rich, the TS girl who took the place of a young lady
It is a collection of CGs in which a TS girl is made to fall into a female state by retribution.

MTL kind of iffy and it almost made me think the protagonist was marrying his own father rather than the man who supported her father.

some clarification would be appreciated.

Base +4, ycanjsd -6, asuke kuzaki +6, BaperNu +9, shadowmist -7, ZAPERINDEX1 +5, BonoBono08 +6, elimere +4

The MC's name is indeed Rei Himukai. The girl is Reika Tachibana, his half-sister (the first kanji of her name is the same as his name). The boy and his mother was abandoned by his father and lived in poverty, while the father went on to marry better and have a successful life. After his mother (who was not a good mother, but he loved her) died, he was picked up by his father's family to act as a servant. He doesn't hate his half-sister, but wants revenge upon his father.

MC finds out that the girl is in love with a young man who is below her station, but that she is expected to eventually marry someone who her father approves of and who will take over the business. He reveals himself to his half-sister and comes up with a plan to take some sex changing medicine and substitute himself for his half-sister. (Amazingly, he looks just like her after the medicine. Blood will tell, apparently.) She happily agrees, exeunt Reika, who marries her boy and they are poor, but happy.

Rei is now living the high life as the ojousama, also waiting for his revenge later. However, one day, his/her father's business gets in severe financial trouble, and his father gets down on his hands and knees begging Rei to marry the man who will save his business, as that is his condition. The man is significantly older, and the idea is fairly disgusting to Rei, but there's really no choice in the situation. (And besides, by marrying into an even richer family, Rei will be in a better position to eventually get revenge on father.)

However, the older man is of course Good At The Sex(tm) and trains her to be the perfect kind of whore in the bedroom that he loves. Rei ends up falling to him, and really has no problem with it, enjoying it. The epilogue is several years later Rei talking to an upper class lady friend about how her dear husband passed away recently. She wonders to herself who her next husband/master (goshujin-sama) will be, thinking that no matter who the gentleman is, she's going to love him so much until she wrings him dry. (I know that sounds like it could be more revenge or sarcasm, but the nature of her internal monologue makes it seem like it's felt quite sincerely.)

Basically it's a TS girl intended to get revenge who instead becomes completely satisfied with her state.

Base +7, Northland +9, misakafgghj +6, pocencer +6, Darksword696 +20, John Abbany +11, 神渊之龙 +6, annast +6, tacobowl8 +10, Rahrahok +6, BaperNu +9, LegoArielFanMaster +9, ZAPERINDEX1 +5, and 10 more...

没理解，这是双重人格还是仆人变性？
仆人变性的话本体去哪了

Base +6, touya03068 -12

@oliger

可惜這部的玩法挺少的，而且功利感太重，對大叔完全就是因為有錢過好日子加上做愛很爽，沒啥愛情在
我還是比較喜歡之前的 "俺が彼女を裏切った理由" ， 金毛追主角的表現順眼多了

@qq471006509

是僕人變性偽裝本體，本體和愛人私奔後就沒描述了，不過以主角這種想要上位的個性，說不定為了避免暴露，私底下把本體弄死了也不一定

可惜後來沒有描述主角有沒有弄死他爸，前面看他挺仇視他爸的

Base +6, touya03068 -12, xy01312 +1, bee926 -6, 厉害了能量桐 +6