/vx/ is appropriate for those purposes, as it has been host to Roleplay threads in the Dungeons and Dragons style for more than two years now, and is appropriate for roleplay discussion topics generally. There are no rules against ERP or explicit images there, as the only board on the website that is Safe For Work is /1ntr/. The ability to upload 5 files in a post has been a feature for several years now. Simply press the little + sign below "Choose Files"
What about /r9k/ stuff?
If its ponies or politics related, the mainboard is fine. Funposting is also acceptable, though /sp/ is the board that allows everything.