Yet another blue door ...
Almost all the action in Essaouira takes place during the day. Local lunch time is around midday. Dinner is after seven pm. There is not much night life in this town. I could only find a couple of beer cafes.
After diner locals go for a walk along the beach promenade. If you want to do something different, you can do a night camel ride along the beach.
I do not know of any disco in town. There are some music bars, but they close before midnight.