• Offices Communication

as said before, the Communication between Offices is as fundamental for the System as highly controlled. It is vital important that no bugs raw system errors be transferred from office to office, as well as it is vital for offices to communicate.
As previously said, no communication or access can inter cur between offices when the Goddess (or Demon) is self present inside the office. The Office Keeper is in his/her self the door&key for access to the office.
Every Goddess or Demon holds a specific spiritual code, given them on birth by the Yggdrasil  Tree System, which allows them to be clearly and unequivocally recognized by any part or member of the System.
There is no way to pretend. The code is unique and rooted in the essence of the Holder. Furthermore, neither the Holder nor anyone beside the Master does know the code for each Goddess or Demon.

When a Goddess has to leave the Office for service reasons, her Angel can be left as guard of the Office.
Since Angels are part of the Goddesses' essence, they as well share a part of their code, hence they can respond to special calls when the Goddess isn't in. However, they cannot replace the Goddess herself. Their code, in fact, contains an identificative pattern that relates Angel to Goddess (that is, the part of the code they share with the Goddess), with add of a special numbering code that distinguish them as Angels.  As far as Communication goes Angels can receive messages from other Offices when Goddess is absent, then forward them to the Goddess herself who, one and only, can decide to get back to the Office in case of particular emergency, or respond directly to the Call Office through External Communication Devices.
The Angel could receive also instructions from the Goddess to be a Close Guard of the Office: in this case nobody would be able to access to the Office not even through Call System (plain communication), but any message would be bounced back.




• Language: someone happened to ask me which language we use to communicate. Simple. It's Yggdrasil coded language, which we cannot disclose to you, sorry.

What I can tell you, is that it's a alphanumeric +spiritual code and it cannot be accessed and used if not by Yggdrasil System Members.
On the other hand, for vocal communication, we use a language that's extremely similar to English.
Surprised? 



• External Communication

not as complicate issue as you can imagine. There are several devices that can be used as E.C. Device. Every Goddess (or Demon) can teleport or message via a specific medium, and her/his code would immediately identify her to the Boundary Guard of Yggdrasil, that is the Protection System directly linked to Maintainance Sector of Yggdrasil Helper Office. Once External Access is granted, the Goddess (or Demon) will enabled to communicate to the System via a privileged and secured line. All communications must be in Yggdrasil code or otherwise encrypted. 
Some Special Ext. Devices have been set in various dimensions to ease and contemporarily secure the access to Yggdrasil from Outside. Such devices are built and work off same material, roots and operative system as the Tree System, and can be compared to Ext. Servers. They do not (nor might) collect any form of data nor they cache informations from communications on work nor in off line mode.
In other words, they are sort of telephone boxes with direct connection to Yggdrasil.



• Wishes Mode : some Offices (the Helper Offices, in particular) are enabled to relieve pain and grant wishes of Dimensions' Inhabitants. There is not one particular way to get a wish heards and granted. There are many ways to get a wish heard and granted. No Goddess knows. The Yggdrasil Tree System selects wishes, the Master picks them up. The Goddess receives the Call and solves her duty granting the Wish.

In some case, a Goddess can point at  the Master some affliction that to her point of view would need special attention. The Master may or may not decide to have the last word on it. There have been circumstances in the past when the Goddesses were allowed to pick wished according to their own feels. It's unsure if this method would work smooth and safely, though. Some Goddesses suffer from an impressing emotional trend, and some ratio shall really be used when granting wishes. As my old friend uses to say "the path to Hell is paved with good intentions".

is the mode created by the Master to keep the two opposite forces of Yggdrasil to crash one against the other (and thusly dissolve the System itself). 

For those of you familiar with Mr. Fujishima's tale, the ICU System is the corresponding of the Doublet System in the comic Aa! Megamisama!. 

The System works simply and smoothly. One Goddess and one Demon are paired  by birth. They will then share experiences, joys and sufferance. Though this does not give neither the Goddess nor the Demon the opportunity of actually controlling one another (the two parts rarely even do encounter, or touch), it's clear that any happy beam or sadness or pain inflicted to either the Goddess or the Demon, would affect the other side of the couple. Furthermore, if one were to die, the other will die as well. 

You can see that since neither Goddesses nor Demons will ever die of natural deaths ^[1], the System should work as a considerate mean to prevent both races from killing one another. And, although in the past some Demons did not regret to kill one of his race along with a hated Goddess, the ICU System has given quite satisfactory results. Both Demons and Goddesses has found other means to fight and contrast one another, more or less willingly improving the functionality of Yggdrasil. 

The success of the ICU System majorly depends on the sentiment, deep rooted both in the Goddesses and in the Demons lineage, that it's the highest crime to kill a fellow creature. 

A Demon/Goddess that would kill a fellow creature, either directly, or as a consequence of the murder of a component of the opposite shore,  would be banished by Yggdrasil, confined in a secure space, and lose all his/her powers. 

If this sounds lame to you, or if you think that a Demon would care less than a comma of fellow creatures, if only in order to kill one of those nasty Goddesses, you don't know Demons. They (like Goddesses) do have a code of honour too, and they as much respect it as they fear  the banishment. 

^[1] A good example of the differences existing between  Real Yggdrasil and Fictional Yggdrasil. In Mr. Fujishima's AMS tale  
the Doublet System is presented as suffering from a severe leak: in fact, in his (Fictional)Yggdrasil both Goddesses and Demons can die of natural death, which implies that if one were to die, for any reason, the other will follow, for no reason. This (fortunately) does not occur in the Real System. Yggdrasil does not need the life threads of its sustainers to be so fragile, nor we would like  it to.