Dying wasn't the worst thing to happen to Harry Potter. He couldn't remember the actual event, of course. No ghost could. The mind blocked it out, some said. Others claimed it was a blessing from a higher power. Who, after all, could remain sane after death while remembering the feeling of life escaping?
Other than walking through walls, Harry's life remained much the same. He still went to classes, still trained to defeat Voldemort. He wondered, sometimes, why he had become a ghost instead of moving on. The other ghosts all had some pretty compelling reasons- revenge, a love left behind. Harry could only think that he had things to do still. There were people counting on him. And his friends would miss him, wouldn't they? So he was stuck, until he had nothing left to stay for.
Mostly it was alright.It was a nit awkward sometimes, like at dinner, when everyone sat talking and eating, and Harry sat with an empty plate. It shouldn't have mattered that much, but it did. Or when he came across Ron and Hermione mourning him, which in his opinion was a bit premature. After all, he was still there. Just a little dead, that was all. And when that long pause came after someone said something about living life to the fullest, or how you only lived once, the silence was uncomfortable.
Odd too were the glances he got when he had to ask someone to carry his things, or had to go into another room so he could mutter the answers on his tests to a quick-quotes-quill, because he couldn't hold a quill.
It wasn't fair to say that everything about being dead was bad. Worry was a thing of the past. Money would do him no good, so he didn't need a job. He didn't eat, and while he did something like sleeping, he didn't need to do it very often. He was becoming better at wandless magic, so soon he would be able to do things without so much help. And he was immortal, if you took that to mean "never dying," rather than "living forever."
Harry Potter smiled. He would be cheerful if it killed him. After all, he would be dead for the rest of his life.