The Concept
This cartoon is about the Brexit. The Conservative Party became the ruling party in 2015 with Cameron as its leader. One of the promises made in the CP's election manifesto was an "in/out referendum" on Britain's membership of the EU. This promise was fulfilled. Cameron himself campaigned against Brexit, but without success. Brexit became a reality and Cameron had no choice but to resign. The promise was his failure. You can see this as the typical Englishman Mr. Bean, who accidentally creates awkward situations.
