Why is she a doctor in Japan and a nurse in America?
Localization. Probably because "school nurse" is, or at least used to be, a recognized position of employment. I don't know what schools do any more. Apparently they don't even use chalkboards or overhead projectors any more.
why did the scanlation stopped?
Got licensed. We're up to volume 6 in secret club though. Hitomi's brother finally appears.
I don't know if it's against the rules for me to dumped licensed manga, but how about the rest of you suffer the volume 6 cliffhanger with me?
Massive. A doctor is significantly higher than a nurse (in my country the former requires a university education, the latter does not). A nurse can do quite a few medical (routine) tasks independently, but usually works under the supervision of a doctor and can't perform certain actions without the oversight or at least approval of a doctor.
A department within a hospital will usually have one or two doctors in house supported by a larger staff of nurses of varying levels.
Also, nurses don't run imfirmaries. Doctors do.
Aaaaaand that's it. I think the next volume isn't until January.
What do you think? Literal semen demon come to wreck home?
They have something called smart boards.
Which I think are just whiteboards with projectors and sensors that tell the computer where on the board you are writing with the marker.