This is by no means an exhaustive list. It is expected that the other delightful souls on this yacht will add more signs in the comments. Because there are more signs. Trust us.

1. Any time you see anything—anything—else that Jeremy Renner or Scarlett Johansson has ever been in, you know that it's just Hawkeye or Black Widow undercover. And you can't believe that everyone else doesn't know that.
2. You also know that any time you saw Jeremy Renner or Scarlett Johansson that they are really Hawkeye or Black Widow undercover.
3. You know that all of his friends and coworkers call Jeremy Renner by his last name. All of them. You've never heard anyone call him anything besides Renner.
4. You are familiar with the debate about Renner's eye color and you have an opinion that you're not afraid to share. Although that opinion may change.
5. The sound of Jeremy Renner's singing voice makes your ovaries hum with happiness. You seek out this happiness from YouTube on a regular basis.
6. You know that Scarlett Johnasson is hygienic.
7. You stalked the Promptathon. It PWNED your weekend. This ownage shows no signs of stopping.
8. You would sell your sister's soul to get a Hawkeye/Black Widow movie. And then you would stalk it.
9. You already stalk IMDb to see what Hawkeye and Black Widow will be in next. (Notice the names used there – not an accident.)
10. You love everyone in this bar, and you really do feel like they're your drinking buddies now.
11. You go back and forth on the issue of whether or not Black Widow and Hawkeye should procreate. You think you've made up your mind, then you read that other fic and you change your mind. Again.
12. Rope. 'Nuff said.