"The Vampire Diaries" is all for steamy hook ups ... and it looks like one particular roll in the sack resulted in more than just a night of fun.

On Thursday, April 25, the CW aired the back door pilot of "The Originals" as one of the season 4 "Vampire Diaries" episodes. Dark and suspenseful, the episode definitely drew in viewers - especially when a major jaw dropper was thrown into the mix.

So, what was the "major jaw dropper"? A character that "Vampire Diaries" fans know is pregnant!

Did Damon knock up Elena? Is Bonnie pregnant with a magical baby? What about Tyler and Caroline?

The expectant couple is actually none of the above! Episode 20 revealed that a one night stand that Klaus had a couple weeks ago with Hayley has resulted in the unthinkable - a werewolf baby!

"Vampire Diaries" execs told fans that they wouldn't be taking the "Twilight" route, and they were right. The fetus in question definitely won't be a vampire (for now). A witch in the episode explained to an unbelieving Klaus that since he was born a werewolf before turning into a vampire it's possible for him to have a werewolf child. While we're not a 100% sure that the baby will be a werewolf, the odds seem great since Hayley is a werewolf herself.

Like many who don't anticipate becoming fathers after a hook up, Klaus refused to believe that the baby was his, telling them that Hayley must have slept with someone else. However, the witches and Hayley both insist that the child is definitely his.

With Hayley and Klaus' unborn baby as leverage, the witches in New Orleans demand Klaus' help in ridding the city of his protégé, Marcel. But while threatening the baby and Hayley's safety might have initially seemed like a good idea, the witches did not anticipate that Klaus might reject them both.

A little time, and some gentle words from Elijah, led Klaus to finally realize what he wants - to be King of New Orleans with a strong family ... and an heir.

So, does that mean he's ready to step up to the plate for Hayley and the baby? The baby, yes ... but Hayley's life is definitely up in the air.

In episode 20, Klaus calls Caroline from New Orleans, leaving her a voicemail and telling her that he's in his favorite place in the world and would love to take her there one day.

Klaus' love for Caroline is definitely deep, so we wouldn't expect him to just drop it so quickly. However, it does have us afraid for Hayley's life post-baby.

Would Klaus keep Hayley around? Would she be forced to leave after the baby? Or will Klaus simply just kill her? Fingers crossed "The Originals" goes to series because we're excited to find out!

What did you think of episode 20, "The Originals?" Sound off in the comments section!

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