I guess the advantage to having something 'virtual' such as the LSF is that you can imagine it any way you like. My own view of it would be something far less grandiose than that shown in the image. I see it as a relatively modest building with very much a retro feel, lots of old wood panelling and a few leather seats here and there.
Two floors to the building, the main one and then a basement. On entering I see a spacious foyer with our noticeboard and other announcements pinned to the wall and then just beyond the foyer we have the reception desk, supposedly manned by the Head and Assistant Librarians but more often than not they've both cleared off elsewhere and probably up to no good!
Close to the reception desk there are book stands showing our latest e-books as well as copies of the most recent acquisitions. I see a large queue of people by the latter, ignoring the library's vast content and jostling to read whatever's just come in instead

I then see all the submissions on a series of bookshelves in the main part of the library with a series of other rooms, some public, some private, adjoining. The public rooms would include a cafeteria and anyone who's familiar with BL will know what delicacies flopsy is capable of serving up. There's a soundproofed audio room with a jukebox and several kiosks with headphones in for the purpose of listening to our musical offerings and audio narrations and a general meeting room where visitors can get together to talk amongst themselves (chat room).
Then we have a number of private rooms:
Head Librarian's office: likely to be extremely untidy and littered with piles of manuscripts, chocolate bar wrappers, empty bottles of whisky, lots of indoor plants and remnants of bombay mix scattered about the floor.
Assistant Librarian's office: contains several filing cabinets, the drawers of which are filled with crisp packets and a variety of chocolate bars. There are several glass tanks containing a variety of creepy crawlies and the walls are filled with pictures of horses.
Staff office: a place for all the LSF staff, including the validators, to hang out.
Miss Thrashbottom's office: The less said about this the better but let's just say it contains a large variety of spanky implements and several 'restraining' devices.
That's about it for the main floor, apart from the toilets of course. Then we have the basement which is where I hang out. No windows and generally very little light, a mass of computers and comms equipment and a large fridge containing cans of faux Red Bull.
I guess that's about it, except to say, that in addition we have a plain clothes security officer/bouncer responsible for evicting anyone who might be misbehaving and by misbehaving I don't mean trying to sneakily whack one of the follow library visitors across the backside when they think no-one is looking.

Anyway, that's my vision of the LSF and of course it's open 24/7...
