Fairy does ×2 to Dragon

Generations VI to IX, single types. The other way round, Dragon against Fairy, is ×0.

64 Fairy and 70 Dragon species among the 1025 this site covers.

Attacker, Psychic and Fairy Hatterene sprite

damage×2Generations VI to IX

Defender, Dragon Goodra sprite

Goodra #0706

Fairy did not exist in Generation I and Generations II to V, so Fairy against Dragon has no value there.

Strongest Fairy attackers

Hatterene leads Fairy at Sp. Atk 136

Sturdiest Dragon defenders

Dual types that change the answer