Hi Wolf,
Taking into account the main subject matter of this particular dream, inviting me to take a "poke" at interpreting it was probably not the most appropriate word you could have used, if you get my drift.
But seriously now...........
Surprisingly at least to me, a girl guide in a dream is often believed to represent exactly that - a female aspect of your own unconscious mind which has been created specifically in order to guide you - literally a guide of yours who is also a girl.
Cathedrals (big churches) are regarded as representing things which are sacred or are normally seen as being taboo behaviour in one's waking life.
Now hopefully your moral values would be offended if I were to suggest to you that you would even consider such a sacrilegious and immoral act as having group sex with girl guides on holy ground in real life.
But because such moral values are frequently temporarily suspended, often for the purposes of shock value or dramatic license with the intention to more firmly impress the message contained within the dream upon you in no uncertain terms, your inner dream director is probably merely reminding you that putting aside your own values in your waking life as you did within your dream orgy could have a significant negative impact in the future on how other people would treat you.
It is certainly not in any way predicting that you could eventually commit this particular act of irreverence, but is simply I feel giving you a timely warning of the potential consequences of your actions upon your personal reputation and standing within the community, if you did ever think of doing something which you knew was wrong, but also found difficulty in resisting the temptation to do it regardless.
A behaviour of yours in real life, which probably has absolutely nothing whatsoever to do with girl guides, cathedrals or for that matter sex itself?
EoT
![Image](http://fc04.deviantart.com/fs11/i/2006/240/a/e/detective_by_ID_entity.gif)