1. The First Time You Don’t Schedule Weekend Plans
That seamless transition between having to wait until Wednesday to ask “What are you up to this weekend?”, and having it be a given that you two are going to hang out.

2. The First Time You Meet Each Other’s Friends
This usually happens casually, in the form of meeting up with people for a drink or stopping by a party, but make no mistake: meeting each other’s friends is a big deal.

3. The First Time You Spend A Night In
Finally getting to the point where a Friday night can mean take-out and a movie at home, rather than a date date.

4. The First Time You See Each Other “Au Naturel”
You’ve probably already seen each other “strategically naked”. This means that while technically you’ve removed your clothing, you still have the aid of sheets, pillows, dim-lighting, and natural looking make-up which you sneakily re-apply in the bathroom.

Seeing each other naked naked for the first time, unbrushed hair, blotchy skin, stubble, and, for women, without make-up, means you’re pretty darn comfortable with each other.

5. The First Time You Call Just To Talk
Maybe you called about something else, or to schedule a date, or to check up on something. But then, once this information is exchanged, you don’t immediately hang up. You find you have lots of things to say to each other, and before you know it, half an hour has gone by. It’s not just physical: you two are in serious like.

6. The First Time You See Each Other Really Drunk
You accompany them to a party, they overdo it, you take them home, they get sick, then sad, then wild, then pass out…and you still like them the next morning? It’s love.

7. The First Time You Talk About Your Exes
Everyone knows not to mention an ex on a first (or second, or third) date, but eventually the subject is bound to come up. Talking about each other’s exes and dating histories shows that you care about a person enough to hear all the gory details of their dating life.

8. Seeing Each Other Sick
Being sick means feeling tired, vulnerable, crabby, and gross. Letting someone see you when you feel that way, (and conversely not being turned-off by seeing someone that way) is a sign that things are getting serious.

9. The First Time You Just Go To Sleep
We’ve already established that sharing a bed with someone sucks. If you’re willingly doing that, and you’re not even hooking up? You must really like each other.

10. The First Fight
You’re comfortable enough to express discontent or frustration with each other — and committed enough to not just walk away. The first time you fight, and survive, you can rest assured that both of you are committed to seeing where this relationship takes you.

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