Arusu wants to live in a magic-using world in
Mahou Shoujotai Arusu (aka "Tweeny Witches"), and one day she gets her wish. A world of magic casters turns out to be a lot darker and more complex than her dream, though.
Nina Fortner's struggle in
Monster to reveal her past and find her brother might vaguely fit, I guess. The world of
Monster is pretty gritty, though, and not very paradisical.