His daughter might be a little…too ambitious.

Hear me now, obey my command; where we touch, our skin shall brand. Until our love to full blossom grows, we shall follow wherever each other goes. /In which, Natsu and Lucy get a little stuck…literally. NaLu/

And in the years to follow, Lucy would come to perceive that Natsu never backed out on his promises. No matter the cost to himself, he always kept them. Every single one. Based off the ED of the FT reboot.

It was like his heart was just saying: Her. It has to be her, and no one else.