If you are using the multi-tenant module. Users are stored in an entity called TenantUser that inherits from system.User. So you would just have to create another line coming out of the inheritance split and cast the correct object.
Edit: I just realized I forgot to mention that you need to create a new page for tenant user if you go this route. I looked through the multi-tenant administration module and they have a smilar microflow that you can use. The microflow is located in the "USE ME" folder > All user roles > ManageMyAccount