DLSite: https://www.dlsite.com/maniax/work/=/product_id/RJ407682.html

Synopsis:
Adventurer becomes the little sister to the succubus reception lady at the adventure guild.

我是高中生侦探工藤新一，有一天在偷看神秘人进行肮脏的py交易的时候，没有注意到一个背后来的同伙......下略

Base +5, markiño +7, heykenny +6, @sdjun +6, LINNNN +6, luo100 +6, smart747 +5, The Stars Like Dust +9, yunnch +6, Crossflash +6, yoo147 +6, sanbai8 +3, thewrold -4, and 30 more...

就連在本子裡面 冒險者櫃檯的小姐也變成了神祕強者的角色了嗎

Base +6, luoqingchenn +5, markiño +7, meigu +6, VK4502e +6, tail red +6, sunsec +5

终于看到正常使用魅魔尾巴的本子

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我超，火箭速度

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有大佬烤肉吗

Base +6, 姒白糖TvT +5, xybsxy +1, dedede2 +6

这男主名字叫阿斗酱，

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公会会长被灌了那么多尾巴汁居然还没被同化吗

Base +5, 白人牙膏 +6, Yami_Neko +6, sunsec +5

丝袜控的我拳头硬了，为啥没有正常形态的啊

Base +6, sunsec +5, 有栖川 +6

我看这男主没变的时候就是一脸受相

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想起那个村子的噩梦

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芳文社著名女演员是怎样炼成的

Base +6, Martjn +6

很好的展现了魅魔尾巴的正确用法，不像许多作者都只是把尾巴当摆设

Base +6, ChrisClauz +6, Azuelle +6, screaming0523 +7, Davinesai +6, yangtidu +6

沒變的時候就是正太，還挺可愛的，應該挺適合女裝

Base +6, dedede2 +6

可恶，要不是这里的魅魔是蓝皮我早就冲出来了……

Base +3, screaming0523 +7, 优雅的二货 +6, Yami_Neko +6, Richard Tai +6, yangtidu +6, 有栖川 +6

满昏，必须满昏

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求烤肉👿👿👿👿

Base +6, 毒之身 +6

不是 男冒險者一直變女, 那她們要吃什麼...

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Succubus-ify the knight?

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Summary of the plot for people:
Ard is a novice adventurer and likes the Receptionist of the Adventure Guild, Anna. People have been going missing in town, and it's localized in the area of the guild. She asks him to investigate a mansion, where he finds it's being used as a brothel and a succubus is involved. Anna was just going to prey on Ard like all the previous ones, but he was able to sense the succubus was actually Anna. Because of this she shows interest in Ard and decides to turn him into a succubus instead and make him her imouto. She stabs him in the belly with her tail, which transforms him into a girl and he passes out. The next morning Ard wakes up and finds out it wasn't a dream and Anna tells Ard the process was only partially complete and she wanted to make sure they were awake. She furthers the progress and Ard now has wings and a tail. In order to not be discovered and killed, she transforms Ard back into a human form that will last half a day and introduces Ard as Kanna, a new receptionist.

At lunchtime, Kanna asks why they aren't going to the dining hall, and Anna tells her they're going to the "exclusive succubus dining hall" where Kanna is forced to "feed" from the gloryhole and becomes addicted to it. Kanna eventually tries to tell Star-san, the Guildmaster, that Anna is a succubus and she is actually Ard that was transformed by her. To which Kanna finds out that Star-san has long since been under the heel of Anna the entire time. To reduce risk and guarantee a "stable food supply" Anna devised the plan to become the guild receptionist and when she wants to feed, slips them the "mansion investigation" request. Kanna is still trying to fight the succubus urges, but Anna points out there's no reason to fight a losing battle and everything will be better if she just goes with the flow. To which Kanna thinks to herself that if even Star-san is under Anna's control what hope would she have of doing anything? So she finally breaks and the transformation progresses to her becoming a full succubus. To which she becomes full deredere for Anna and apologizes for being so stubborn etc.

The last scene is a 4th wall offering the mansion request and saying "You'll accept the request, won't you?"

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