I'm not sure if I follow you(?)
It's the EU asking the UK that they should remain in the EU, because we're stronger united.
The UK then responds by saying to the EU: piss off, we don't need you telling us what to do - we can handle our own business just as well.
Upon successfully voting for the Brexit, N.Ireland and Scotland, which are part of the UK, are saying: "hey, we didn't want this, we want out of this and stick to the EU".
At which the British respond with the same reply of the EU: "please don't leave, we're stronger united".
It's the irony of the two similarities that are exaggerated and put into the spotlight (as is always the case with cartoons).