Trouble removing a group

Hi all, in my groups set up i created a group called [loyal wolf] i have now added a new group to just loyal. However when trying to remove [loyal wolf] it wont allow me. It says 'group [loyal does not exist. Clearly the space in the name is causing some issues. I tried deleting the group directly from the groups data file and it re-appeared. Image below for convenience.

I have tried underscores, dots and dashes and none of these work meaning this group is just sitting there. I know if sounds anal to some people but i like everything to be clean. As most of you are coders i am sure you can appreciate that.

Any help appreciated.

StGeorge