Want Messenger List contact group not to be in general contact list

Title probably doesn't explain well. I want to start a messenger list that is completely separate from my contact list. This would be a list of about 100+ phone numbers (contacts). It would be great if I could create a simple list with these contacts that do not appear and completely clutter my personal contacts.

Even third party apps seem to only work off my contact list without the ability to create a new and unique contact list.

Kind of like Microsoft Outlook where you can have multiple independent groups

Any thoughts would be greatly appreciated.