The SP Corner guidelines, as in previous posts:

Just to note: obviously this is an open thing and I have no concrete power, but as the person who prompted this I’d like to kindly ask:
1. Keep it E for Everyone. Please no suggestive artwork.
2. Pride flags are fine, just not, like, a hundred of them everywhere taking up space. Thanks. (Fortunately has not been a problem.)
3. Same goes for country flags, of course (also has not been a problem).
4. Leave others’ work alone unless asked. There’s plenty of space, no need to overwrite others’ art. It’s courtesy to respect hard work, eh? Additionally, mind where something is likely to expand into if incomplete; it's rude to cut someone off.
5. Do remember that this site is very poorly moderated, so please, Stay out of Hawaii. This applies doubly if you're on the younger side, seriously

May update suggested guidelines if more things come to mind.