This is not something to fuck around with. A pinky promise is serious. You don't break a pinky promise, that's just shitty...
...it's like kicking someone in the shin, which will happen to you if you break a pinky promise!
Jon forgot about taking Bob to the airport, and Bob missed his flight.
That afternoon Jon's wife, mother, father, and the secretary he was having an affair with all died in a fire during an open discussion about Jon's affair. Jon found all of this out, and then was kicked in the shin and mauled to death by a bear.
This all happened to Jon because he broke a pinky promise.
Also know as a "Pinky-Swear"
You both lock your little fingers together and say "Pinky Promise", me and a ex did this and we split so erm it proves that its true yeah! because the promise wasn't kept and we don't see each other anymore!
Kat: "Pinky Promise?"
Chris: "Pinky Promise!"
*Chris eats a whole bag of Double Lollie's and forgets about Kat, therefore Kat forgets about Chris...COMPLETLEY! lol*