Nothing really "bothers me" about this manga. It's just boring. Just your typical shoujo manga. Nothing more. Quite plain and predictable. I got the feeling that you read it expecting some kind of development but nothing is really going on. The summary is good but having read 9 chapters and getting almost zero plot in them it's an issue. Well another great idea wasted.
The characters are okay. Very steoreotype ones. Not sure I like the female lead.
The art is really cool, I liked it a lot but it wasn't enogh for me to keep reading.
Read it if you don't have anything more appealing.