I have to agree with the comment below mine, about both the grey on black font, that made the story a little difficult to read, and the lack of spacing between paragraphs.
Other than that, I really enjoyed it. I love the Avengers, and it really seems like you grasped their characteristics quite well. I could totally picture Tony behaving the way he did at the beginning. I also loved how the Avengers interacted with each other.
The premise of this story was really cute, and unique, and I think you're doing a great job with it!
I typically don't comment on layouts in a swap because I can't stand it when people only focus on my layout and not the actual content of the story, but I did have to switch to the default layout because the gray text on black was impossible to read. I also have to mention that it's against the rules to not put spaces in between paragraphs, so this story could get reported for that.
Moving on to the actual content of this story, I have to begin by saying that I'm not familiar with the Avengers, so if I'm a little clueless, please forgive me I really enjoyed the premise of the fic, and I thought the dialogue between the characters sounded realistic and flowed very naturally. My only suggestion as far as concrit goes is that I would have loved to have seen more description in this first chapter.