Stunningly GORGEOUS! I've read this several times now and just keep finding favorite parts.

“We are Clint Barton and Natasha Romanoff. They’ve been friends for more years than anyone thought possible and, lately, things have been heating up but they’re taking it slow because they both have things in their lives that makes a relationship hard to deal with. I suspect, given the proper timing and the right circumstances, they’ll eventually work it out.”

AND:

He used the word love like anyone else but she could tell it had meant something different to him. Something deeper. Something stronger.

Her feelings mirrored his but she couldn't admit that without having to discuss what love meant... or didn’t mean. Nothing as strong as what she felt could be contained in a four-letter word. There were other words she preferred using, having once looked up the meaning of love in a thesaurus. Attachment. Adoration. Fidelity. Worship. Ardor. Allegiance. Yearning. Esteem.

I think I've finally narrowed it down to those two parts. But I think I'll have to go back and read it again just to be sure!