Small spoilers
This review includes some spoilers which should not ruin your experience if you decide on reading this work.
Deus ex machina issue
The author very much likes to assign mandatory missions to the protagonist using the system. Mandatory as in, either do it or die. Apart from that, early on, MC receives a penalty for failing a quest that makes her randomly lose control of her body. In those instances, she behaves like a regular baby. The author uses both of these things to make MC behave like she wouldn't normally and force the plot to progress in certain ways.
Powers
MC's promised powers manifested in form of a system, which she can use to buy powers of protagonists of RF novels she read before. However, if there are multiple powers, only one will be extracted at random, there are limits to number of uses and even the powers themselves can be massively weakened because of system's whim.
Here's the premise of the arc containing MC's first usage of powers with as little spoilers as possible:
Spoiler, click to view
MC gets a quest from the system asking her to get revenge, with the penalty being increased probability of losing control of her body randomly. MC decides to accept the quest and uses the system to acquire new power allowing her to read target's emotions and thoughts. However, the power has only five uses lasting three hours, and gets downgraded to only reading emotions because "This is a dropped novel and the system isn't familiar with it". The power itself ends up being completely useless anyway, and the author just uses it to show just how mad the revenge target is using some poor jokes.
From the beginning, MC isn't able to recognize even the most basic tropes when they actually matter, only using the knowledge she was supposed to have to show that the author is self-aware that his work isn't really groundbreaking, like making jokes about her father, the duke, being the "classic emotionless duke of the north". In my opinion, her knowledge of novels was added solely because the author needed it for the power system to work, since it doesn't have impact on the story in any other way.
ConclusionIn general, it looks like the author wants to have the cake and eat it, so he uses deus ex machina to achieve it.
- MC is a reincarnated adult, but she doesn't behave and think like one 90% of the time. When she actually would behave like one and the author doesn't want her too, he just makes use of the penalty system making her lose control of her body and act like a regular child.
- MC "read thousands of RF novels", which is used to make use of her power, but is incapable of actually recognizing tropes when they matter. A prime example of that can be seen at the very beginning:
Spoiler, click to view
MC is abused by her uncle and her cousin, and she says that if this was a novel, her cousin would obviously be the beloved protagonist. So the obvious protagonist of a romantic fantasy novel is someone abusing their cousin on daily basis, and not the abused cousin, who is daughter of a powerful duke?
In conclusion, everything in this story seems kind of forced and I wouldn't recommend it, but if you just want to read something with a cute girl as a protagonist then this isn't the worst choice.
If you want something similar, but much better and without a system, I'd recommend reading "Who Made Me a Princess" if haven't tried it yet. It's an absolute classic in this genre.
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Another two recommendations would be "Becoming the Dark Hero's Daughter" and "The Male Lead's Little Lion Daughter".
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