For instance:

clacc Linked : Entity {
    .....
}

clacc A : Entity {

[Association(OnOwnerRemove = OnRemoveAction.Clear)]
public virtual Linked {get;set;}
}

clacc B : A {
[Association(OnTargedRemove = OnRemoveAction.Cascade)]
public virtual Linked {get;set;}
}

This is really necessary for intermediate Many-to-Many type definitions. I want to control what happens in inheritors of my base type Multilink<t1,t2>