(s) one which receives or benefits from a specified action: addressee.
(s) One that possesses a specified thing: mortgagee.
(s) one which carries out a specified action: absentee.
A suffix made use of, mainly in law terms, in a passive signification, to indicate the direct or indirect object of an action, and/or anyone to whom an act is done or on whom a right is conferred; as in assignee, donee, alienee, grantee, etc. It is correlative to -or, the broker or doer.
How would you define -ee?