one of those regimes that they just choose/install someone else and keep going

The council (50+ members) may elect another leader in his stead, provided the current council can hold on to their seats, which depends on a lot of factors.

If it falls, will the democracy kick in or a civil war

If the previous Western policy for the region is any indicator, they'd prefer a monarch over democracy. Probably even civil war over democracy, but ¯\_(ツ)_/¯