Accidental Marriage

As to the real-life possibility of an Accidental Marriage being valid (at least in North America), it's pretty remote: although courts in both the U.S. and Canada have decreed that a couple who thinks they're legally married is legally married, at the same time a marriage usually isn't considered valid without a marriage license, which has to be purchased before the wedding (and in most places both parties to the wedding have to buy the license together). This was originally meant to prevent marriage fraud, but it also allows the state or provincial government to make a little money on each ceremony.

Additionally, the "getting drunk and waking up married" type is not valid either, since the law requires that both parties enter into the relationship voluntarily and in full possession of their faculties. (This is nearly always in Las Vegas in the US version, due to the fact that unlike many states Nevada does not require a waiting period between obtaining the license and the marriage itself, and that the Clark County marriage bureau office in Las Vegas is open until midnight every day of the year, even weekends and holidays.)

This is where Nick Jonas and Demi Lovato story starts. Nick Jonas who is still dating Olivia Culpo and Demi Lovato who is still dating Wilmer Valderrama. Well all about to change when Nick and Demi went to Las Vegas for a meeting for the next upcoming concert tour. They party and got drunk. ( Yes I know Demi is sober but this is full on fantasy it makes my storyline worth writing about.) Woke up in bed together and just find out that they are married. What about their significant others,families, friends and fans. Oh boy.