You're in the demo.
Three fictional clients with made-up people. Look around freely: nothing can be changed, and it all resets every night.Get Office Sentry
0 of 4 can be signed in to directly. These accounts don't need a password; an open one usually has no MFA and nobody watching it. Block sign-in in the Microsoft 365 admin centre (Users > Active users > the mailbox > Block sign-in). People keep their access.