How to define a create nested XSOData endpoint

Nested may not be the right wording but I am trying to create a XSOData point for creation with the bellow URL. I am trying to use it make an entry into table User. The entry into table table may end up being done with a stored procedure if need be.

http://someserver/Groups(1)/Users

There is currently a working endpoint with complete CRUD for Groups. Its entry in the .xsodata file looks like the following

"##CLOUD_SCHEMA##"."BI_GROUP" as "Groups"

I am able to get an entry into the table for groups via the below URL and .xsodata entry, but it is not logically optimal.

http://someserver/Users

"PHOTON"."BI_GROUP_MEMBERSHIP" as "Users"

The Users entity is mapped to a relationship table is best (for purposes) seen as an element of the Group. Any thoughts?

Thanks,

Johnpaul