This is the first time I have seen an odd request like this. I don't know if the staff can grant your request but in case they can't, your alternative would be to request a self ban for 6 months which is the maximum time period.
Well, I don't plan on playing anymore, so there really is no need for my in-game account or my forum account if you know what I mean? I'll ask the GM directly then.
You can ask for it on the Character Issues or Report Abuse forum rooms. I don't know if they would ban your forum account, but they can ban your account and unban in the future if you want to. Some people do that to secure their accounts on big while breaks for study/work.
