1. When you get dressed in the morning, there’s a mental matching game that happens comparing the day’s activities ahead of you/their potential to lead to sex and the underwear you have on. If there’s even the slightest possibility, you’re armed with your finest underthings.

2. After dressing but before exiting the apartment, you assess its level of disarray to see if it would be passable for company.

3. If it isn’t passable and the possibility for sex is real, you’re not above hiding things under your bed or in the oven.

4. When switching purses, backpacks, briefcases, pants, etc., you make sure your condom stash carries over.

5. You know your roommate’s schedule as well as your own. It helps to know how crazy you can or can’t get that night.

6. You’ve perfected a million different vague-yet-polite ways to say, “I’m busy then but what about [insert next available date]?”

7. You have a favorite place to get tested.

8. Your iPhone’s message preview feature is turned off—that shit is NSFW.

9. Along the same lines, your read receipts are also off. Sometimes crafting a response (see #6) takes a minute, especially if you’re out on the town.

10. You always try to host at your place; it’s easier & minimizes the stuff you have to carry around with you.

11. You also probably have a foldable toothbrush for when the aforementioned hosting doesn’t work out.

12. You realize that the term “good in bed” kind of means nothing—it’s all relative. So as long as you fall within the adequate range of performance, you’re probably worth sleeping with again. Only the outliers ever stick out.

13. When making back-to-back plans for the week, you automatically do the quick mental math of when the most logical times to shower would be.

14. Speaking of showering, you always have extra guest towels on hand. You’re not going to say no to the “Do you mind if I rinse off?” line, but you’re also not about to relinquish your fluffy good towel.

15. You have a go-to bar and breakfast spot you frequent near your place for pre- and post-coitus, respectively.

16. You probably have a rotation, and you’ve picked up quickly on the roles each person can play in your life—you know who to call when you only have an hour. You also know who’s coming over (and who definitely isn’t) while you’re on your period or getting over a cold.

17. If/when you enter into a serious relationship, you’re not the person to initiate the “What’s your number?” conversation. Don’t ask, don’t tell.