A starting point could be the studies on the unconscious alliance existing between subjects that in some way or another are tied together. There are authors that have produced significant works on this subject, therefore I feel it's worthwhile to make an attempt, if only provisional, to synthesize this progress.
Didier Anzieu demonstrated that a group, (his idea could include other sorts of ties), cannot organize itself nor stay alive if it doesn't conform to the following: 1) it must satisfy the adaptive needs of its members, (i.e. how to survive in its environment, and effectuate all their possibilities); 2) it needs to contain, acknowledge and favour the development of the components' respective, fantasy worlds.
Two types of organizing forces are established that interact, they can reciprocally increase their strength, or otherwise hinder each other. This is what Bion meant when he described group work and the basic assumption. Our own experience has amply demonstrated that this does not come about only in small groups.
When there is a bond between members they must come to an accord on their expectations regarding the level of the secondary process, indispensable condition for the realization of a shared project. They must also come to a sort of adjustment in their reciprocal relationships, that enables each person's needs to be satisfied (within the togetherness), and also to enable the projection and the satisfaction of their unconscious motivations.
This agreement or accord is expressed on two levels. The first level is manifest, where there are no evident, complex problems: social psychology with its concept of “motivation”; habits, laws etc. provide the means and the models for establishing adequate guidelines for forming effective ties. The second level, on the other hand, necessitates comprehension of how the unconscious enters the picture in these ties, and what effect it has on the relation itself, and its single components.
We will begin these reflections with Freudian metapsychology, taking into account that even if these models imply the individual, psychic function that for the most part has to do with the function of the internal elements that condition the apparatus, the material for creating ties is produced by the subjects themselves.

Thus we need to see if the metapsychological models allow an exploration of this interstice, and if it is necessary to establish a modification ad hoc between them. 
Freud elaborated various metapsychological models, and at the end of his works he 
introduced the problem of intra-systematic splitting, corresponding to the splitting of the ego in the defensive process. J. Bleger working in the field of theorization 
close to M. Klein, took up and developed these ideas, applying them specially to the study of borderline pathology,(the general psychopathological picture and the therapeutic capacity of the analytical method). He put the accent on the splitting of the apparatus and the preservation of a layer separated from the rest that functions according to special laws. He described the effects of the depositing of this layer in subjects that have ties, resulting in the forming of a syncretic sociality (trans-subjective) between the members, a sociality that agrees with that of the role. He also described its projection and fixation on the elements of the psychoanalytic setting.

Clearly Bleger's position along with other contemporary Argentine authors1 gives nuances to, and almost modifies the Freudian metapsychology, (here I am referring in particular to the second topic of 1923). I will attempt to outline a possible model of the above-mentioned topic, using as an example A. Green's double boundary model. I will add some personal reflections that could help to facilitate its use in studying ties that have a significant, narcissistic content. Green elaborates his model starting from the topic of 1915, to which he adds the boundary between the apparatus and the soma (to the left), and the boundary which establishes the external world (to the right).
The arrows above the diagram indicate the extension of the categories created in 1923, Ego, Super-ego, Id, the place that will roughly correspond to them in the topic of 1915. The external world is where the ‘other' lives: thus it is the place of the ties with the external objects.
The two extremes of the apparatus: the boundaries with the external world and with the soma were created contemporaneously from a genetic point of view. The encounter with the ‘other' gives rise to the emergence of the apparatus that produces with that very action, its boundaries. The representations of ties with the ‘other' – and subsequently with others – gradually form a psychic web that becomes more and more complex, acting as an instrument to comprehend the external world and corporeal stimuli. The boundaries created in the two extremes of this apparatus are therefore an effect of the structure that contains them.
The impulse is necessary to this process; starting from the soma it reaches the apparatus where it is transformed into its substance. For this reason it must find a representation that will come from the ‘other' and give it meaning. During the course of its development, the apparatus reasserts its boundaries, with both the soma and the external world: at the end of the elaboration of the Oedipus complex, the difference from the ‘other', the introduction of the subject into sexual differentiation and into the chain of generations, is achieved. The formation of the Super-ego at the end of this stage allows the affirmation of the neurotic structure, with the possibility of development (or retrogression) of its specific conflicts.
Its important to keep in mind the formation of the primary repression. Many authors have expressed their different views on the constitution of this defence mechanism; Freud himself, was not very clear in his definition of it. In my opinion, primary repression emerges in the very moment that the first perception of the alterity of the ‘other' occurs, being a sort of initial representational ground expelled from the psychic apparatus, (and confined in a special area that we have called primary unconscious) (P. Auligner, 1975) where the fusion between subject and object is preserved.

I believe that what Bleger called ‘adhesive core' is none other than the contents and the structure of the primary unconscious. Its substance is not that of the unconscious fantasy as in the case of the unconscious so as to speak, but is an elementary outline of a psychic structure, close to the pictograph that P. Aulanier (1975) spoke about, or the formal significance (D.Anzieu, 1987). In this way two spaces are differentiated in the psychic apparatus: the one described by Freud in his topics, and the primary unconscious, the ‘adhesive core' (Bleger), separated by a barrier of splitting.
One could consider that as a result of the encounter with the ‘other', the development of the ties between the different layers of the unconscious will take on 
different shapes and will impose different rules. We have defined the agreements as being conscious. How shall we consider what is produced from the exchange between unconscious fantasies that are characteristic of the repressed unconscious? Kaes points out the essential organising quality and the power of attribution and topic distribution of the spatial development of these fantasies, specially the primary fantasies .
In his description of the group psychic apparatus, D. Anzieu maintains that the unconscious projection of the subject gives rise to the exchange of fantasy contents to such an extent among the subjects that they enter the group like a dream, and get a similar result in satisfying their unconscious wishes. Everything that is manifest in these ties, functions as the day's residue, available to be worked on by the unconscious development of the participants. This is fundamental particularly for the members of a small analytic group of formation insofar as its particular structure favours this dynamic, but one finds it partially occurs in any situation where there are ties among subjects.
The contents repressed by the single subject include the ‘other' in their projections, they modify him/her (the work of the transference), sometimes amplifying the 
qualities or suppressing them. From these effects the bond is either enriched or nuanced by them and assumes a complex interface. One can consider these vicissitudes a condition for the creation of the unconscious agreements; when they become accepted and respected by the different sides, the bond or tie has to be able to sustain one of its functions, namely be a support for the projections of the repressed unconscious. The substance of this development, already treated by me in other studies (Bernard M., 1995, 1996), could be summed up as a dramatic sharing, the development of a space for unconscious dramatizations, more or less linked to verbalization.

Psychoanalytic work, here as in the dual setting, must aim to enucleate the repression, amplify the field of the conscience, and resolve neurotic transferences. Going back to the previous comparison regarding the mechanisms of the dream, I believe that when the activity of the togetherness of the ties becomes too separated from the manifest pact, a mechanism of secondary elaboration is activated that tries to restore the logic of the secondary process to the situation.
The problem of the repressed unconscious is completely different. It is situated in a previous point in time in the primal repression, that is created at the moment of the splitting of the psychic apparatus. The separated unconscious exists in all subjects and embraces more or less what space is available. The possibility that disorders appear depend on this quantum: its development is not necessarily pathological, however an excess gives rise to a wide range of borderline pathologies. It's interesting to note from the scheme I proposed, in as far as the location and the function are concerned, how it corresponds to the Freudian exemplification of the Id.
In this context it's impossible to speak of agreement or harmony. If its primordial characteristic is to deny the limits of the apparatus, resulting in the non-acknowledgement of the limits of the ‘other' then there is no way an agreement with someone or something that cannot perceived can come about. 
How can one imagine a mechanism of adjustment at these levels? Since this reality is present in the functioning of symbiotic pairs, in bureaucratic groups, in sects, in the families of psychotic patients, one can realize its effectiveness in the production of pathology.
If at the level of the conscience and the repressed contents the agreements are made by adding something to the bond that didn't exist in the single subjects prior to its constitution, in the non-repressed unconscious this process implies a hewing out. The narcissistic ideal will not accept anything from the ‘other' that reminds it of its otherness; it therefore acts disavowing any trait that suggests it. If the ‘other' has such a desperate need and is unable to do without the bond, all these ‘unrecognized' traits are abandoned, since they impose a painful anxiety of non-acknowledgement on the desire of the ‘other', and those aspects that the partner can recognize are consecrated.
If both are involved in this tactic, the relation that remains at the end of the 
organizing process is minor compared to what the different parties had at the beginning, as far as the possibilities and nuances are concerned. No agreements come about, since the process comes about in the intimate sphere of each one, even if there is something that often determines a significant reduction in the egoless capacities of each one. 

However no one negotiated anything with the ‘other'. The phrase that one more often than not hears in these ties where a demand for appreciative recognition for a kindness is met with: “But I never asked you…” And it is certainly true.
Previously the resorting to the secondary elaboration in the development of the bond in the repressed unconscious was mentioned. In the case of a fracture that is clearly pathological, this role is expressed by the hallucinatory filling-up of the rejected elements produced by the mechanism of denial.
In literature this type of situation is habitually nominated narcissistic pact or pact of denial. Frequent use and accessibility have contributed to using these names, while it is important to remember that if they are thought of as a type of agreement between sides, one is running the risk of reifying something that exists in a negative sense.
In clinical cases, variables of all these mechanisms in any type of tie or bond can be verified. Bleger had foreseen that the deposit of unbiased aspects in the therapeutic setting was reproduced in all the analyses and not only in those patients with narcissistic pathologies. But the bigger the portion of these deposits is, the
more severe the pathology will be, creating reservations concerning the prognosis of the treatment.
The diagram that follows proposes a definition of these alliances, according to the level of the psychic apparatus in question.

                             Defence mechanism Type of agreement

Bibliography

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