How did the poison get in Joffrey's Cup?

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Tags

1. #poisoned
2. #necklaces
3. #presumably
4. #within
5. #joffrey
6. #tyrell
7. #dontos
8. #crystal
9. #necklace
10. #reach
11. #those
12. #sansa
13. #happens
14. #poison
15. #poisoning
16. #asked
17. #women