What are the clinical features of sepsis?

Multiple. Sepsis is the body's genealized inflammatory response to an infection. One of the most notable features is "capillary leak" - fluid leaks from your blood vessels, so you become edematous and need aggressive IV fluid resuscitation. Organ failures may also occur - confusion, low blood pressure, shortness of breath, concentrated and poor urine output.
Severe... Sepsis is a severe, life-threatening illness. Syptoms often include high fever, low blood pressure and high heart rate. Other symptoms depend on what organs are affected. For example rashes if the skin is involved, confusion if the nervous system, low urine output if the kidneys, irregular heart rhythm if the heart, etc.