Durian has a bad reputation for being a smelly fruit but to me it is simply a very fruity smelling fruit. It smells quite sweet and can be a little intoxicating when too ripe but overall it is fine. The flesh of the fruit is very soft. The flesh looks like a large bean pod. Unbeknownst to the casual observer those bean pod looking things are actually made up of smaller pods that each contain their own small seed. As mentioned before, Durian is rather sweet and it is best to not get an overly ripe one. It is also expensive by Thai standards which is surprising considering there seems to be no shortage of supply and can be found at every market and on the back of trucks that randomly park and sell it. Maybe the demand is just that high for this tasty fruit.
One thing to note: Durian is not allowed in taxis.