You see the dragon eggs
There are incestuous undertones (2 drinks for explicit incest)
Varys talks about his "little birds"
"Winter is coming". You know what to do.
Someone insults Tyrion
Declare your house at the beginning. If you hear the house name or see their sigil, take a drink (2 drinks if you hear their house motto)
Someone brings up Varys eunich-status
Daenerys says "my sun and my stars" and Drago says "moon of my life"
You hear a reference to "The Seven"