Yes, usernames that are offensive are banned until the user selects a new name to change it to. Also, usernames that are the full name of the person or gives away personal information such as phone number are able to be requested to be changed. Each request is evaluated based on merit as to avoid the possibility of someone trying to lie about the name change. For example, if Inga no Kusari mailed in saying his real name was Inga no Kusari, we might require some proof before changing. As Inga stated, its not a common practice.