User Recommendations for This Ugly Yet Beautiful World

Both series have a young boy find a mysterious girl with a hidden darker personality (which arouses jealousy from their respective female cousin), and humorous ecchi scenes occaisionally divert attention from the characters' traumatic childhood experiences.

Elfen Lied and Konomini both share a similar main character, one that is struggling to understand her place in the world all the while trying to go against fate and control the darker side of herself. Besides the bigger picture, relationships also play an important part in both stories. (Jealous cousins included in both.) Lastly, both series can go from idyllic to dark and disturbing in the snap of a finger. (Though Elfen Lied more so.)

similar plots, but TUGYBW is less graphic

Both are similar in some aspects in regards to how an amnesiac girl (or girls) wind up living with some dude, and then there's some crazy shit about the end of the world and whatnot.

Both have a supernatural girl who is being chassed by a strong enemy,and then they meet a guy who the drag into their wolrld of chaos without even knowing why they are being hunted.

Both have easily noticeable connections when the plot elements follow a similar path: sweet and whimsical girls with hidden dark personalities try, and initially fail, to find acceptance in the cruel, "ugly" world. To me, Kono Minikuku mo Utsukushii Sekai (or "This Ugly Yet Beautiful World") is pretty much Elfen Lied without the gratuitously violent shock effect.