Removing a Group from O365/Onedrive

I'm the admin and we recently set up a partner with O365, then set up onedrive for them to share work documents. I was unaware the O365 automatically creates a shared group so I created one manually in a user to share documents. I was in the new onedrive control panel and I didn't realize it until I wen to the old control panel and found one was created by default for that company. Question is I can't find any way to remove/delete that group in the user account it was created even though that user is the owner? Am I missing something on where I can delete that group? Basically how do I delete that unneeded group?