Is possible to delete only the forum account? If yes how?
Forum account deletion
Yes, by an admin, but there is not really a reason to. If you created it and don't want to use it, it doesn't do anything.
"Nerds have a really complicated relationship with change: Change is awesome when WE'RE the ones doing it. As soon as change is coming from outside of us it becomes untrustworthy and it threatens what we think of is the familiar."
– Benno Rice