Two to three years ago, I was reading a very interesting sci-fi manga, but I dropped it and now I can't remember the name. It was not new when I read it, but I'm pretty sure it was released after 2000.
If I am right the protagonist was at middle school. He was an average boy and there were this alien girl as his classmate. The alien girl lived in a abandoned tram, had a black bob cut with bangs, and looked completely normal (although two other aliens were big and detailed).
At some point the girl got in a fight with an other alien at the Ferris wheel and the boy got pierced through heart and then the girl saved him somehow. (It was a bloody mess). Then there was some drama in school at some point and then there was the boy's twin brother, who had long hair, and his alien female friend. I dropped it at this point because I did not like the twin brothers hairstyle.
The art was rather beautiful (in my eyes). It was probably an English version, but I have been reading manga in five different languages for years, so I can't be sure.
It was actually kind of a confusing book. The themes were something like: being lonely, getting friends, and other stuff that could found from Shugo Chara!, but instead of handling fights in a way Shugo Chara! does (so it would be good for younger audience), it handled it like Akumetsu did except there was no guns.