Mal de Coucou. n. a phenomenon in which you have an active social life but very few close friends—people who you can trust, who you can be yourself with, who can help flush out the weird psychological toxins that tend to accumulate over time—which is a form of acute social malnutrition in which even if you devour an entire buffet of chitchat, you’ll still feel pangs of hunger. (Definition courtesy of The Dictionary of Obscure Sorrows)

A play off the French 'Mal de Caribou' which denotes a feeling of starvation even when one is getting enough to eat. This inherent, insatiable human need for more. To know more. To achieve more. To be more. Mal de Coucou plays with this idea of dissatisfied yearning even when one, on paper, should be satiated.