Kdrama fans love a good noona (older girl/younger guy) romance but the upcoming fantasy drama "You Who Came From the Stars" may technically not qualify.

Yes, Kim Soo Hyun, who starred in the hit drama "The Moon Embracing The Sun" and the record-breaking film "Secretly Greatly," is only 25.

And yes, Jeon Ji Hyun, who was his co-star in the film "The Thieves," is 32. While she does play his love interest in the upcoming drama and the woman he has waited his whole life for, this drama is technically not a noona romance.

It borrows a page from "Twilight" in that although his character looks slightly younger, he is really older. A lot older.

"Twilight" fans may remember Bella's reluctance to age and be a year older than her vampire crush, Edward. When she expresses this discomfort he reminds her that, being immortal, he is really 109 years old. Is she really okay with dating a so-much older guy?

Of course she is. Age, after all, is just a number. And he looks 17.

In "You Who Came From The Stars," the professor that Kim Soo Hyun plays looks a few years younger than the famous actress Jeon Ji Hyun plays.

But although he looks young, he is really 400 years old.

Will Jeon Ji Hyun's character be okay with that? Four hundred years is pretty old and, besides that, in 20 years he is still going to look 25. As gorgeous as she is, she will look 52.

The reason Kim Soo Hyun's character is 400 years old and looks 25, is because he is an alien who landed on the earth during the Joseon era. He has become so jaded about human behavior that it has taken him 400 years to fall in love. And its as much a surprise to him that it happens as it was to Edward in "Twilight."

Kdrama lovers often have some big obstacles to overcome when it comes to true love. The person they love can be hard to get along with, a decade younger, have a disability or come from a poor family. But being 400 years older and no longer aging is a big obstacle. Bella overcame it by becoming a vampire but how will Jeon Ji Hyun's character deal with loving someone who is 400 years older?

It's not like she can become an alien?

It's one of the many plot twists that make this upcoming drama look so interesting. Check it out. The drama begins on Dec. 18.