Is there some type of connection between Mavis and Zeref?


In opening 10 of Fairy Tail at 1:15 we see Mavis and Zeref walking towards
each other. When their lines of vision meet, a look of deja vu appears on
their faces, indicating that they have meet before. Do they know each other
and what is their connection? Did they once love each other? (That's the
speculation on my part.)

Please watch the **opening of Fairy Tail, Number 10**
[here](https://www.youtube.com/watch?feature=player_detailpage&v=3sdm2CEhW7A#t=75)
first **before** answering my question so you have a better understanding on
what I am asking in my question.

Answers are appreciated.




~~Until now there's still no flash back about their relationship.~~

From chapter 450 'The One And Only This World' it was confirmed that

> ![enter image description here](https://i.stack.imgur.com/Hg2aS.jpg) Mavis
> and Zeref love each other, and because of Zeref's curse, Mavis died




I think Zeref and Mavis had a thing. You know how Zeref said one day, that he
realized the meaning of life and stopped all of his bad ways? Well, I think
that day was the day Mavis died. Possibly killed by Zeref himself. He may have
felt terrible and realized that he needed to be stopped. So as he awaits Natsu
to get stronger, he stays near Mavis, enjoying her presences till the day
comes.

