This is going to be a short review because there's not much to say about this series.
In the simplest terms, Maou no Musume wa Yasashisugiru is easily one of the sweetest and most wholesome manga I've come across.
This episodic comedy is about a little demon girl named Dou, who happens to be the daughter of the Demon King, Ahriman. As the description states, the Demon King had to stop his goal of conquering the world for the simple fact that his daughter is far too kind. She wants to help anyone and everyone she meets, regardless of whether it's a human, a demon or a little creature. Befriending everyone along the way, the series follows the short and sweet episodes of Dou's daily escapades with Jahy, one of the King's closest advisors, as she tries to turn her into a mean demon, only to fail every time.
And that's kind of it. The simplicity is enough to carry the story forward. It's adorable, it's wholesome, it's soul-healing and leaves you warm and happy and that's exactly what makes this series so good. Coupled with a nice and crisp art-style, the mangaka does a great job in portraying Dou's adorableness and the impact it has on everyone around her.
Highly recommended if you're looking for something sweet and simple to make your day a little better.