In Fable II, after completing the main game, there is a side-quest in which the player can obtain the Potion of Transmogrification. To access this quest, the player must first buy Fairfax Castle (for 1,000,000 gold). Taking this potion will irreversibly change the player-character from male to female, or female to male. A video of this transformation can be seen here.

Following the transformation, NPCs will comment “didn’t you used to be a man?” (if the player-character was male). Any spouses whose sexuality makes them “incompatible” with the player-character’s new gender will no longer have sex with them. In sum, only bisexual spouses continue to be attracted to the Hero.

LGBTQ  references in this game series:

All games: Sex Workers; Relationship Options

Fable II (2008): Potion of Transmogrification

Fable II and Fable III (2010): Reaver; LGB NPCs; Cross-Dressing

Citations:

1. Castle Fairfax (quest). (n.d.). Retrieved from http://fable.wikia.com/wiki/Castle_Fairfax_(Quest)
2. Fairfax Castle. (n.d.). Retrieved from http://fable.wikia.com/wiki/Fairfax_Castle
3. Potion of Transmogrification. (n.d.). Retrieved from http://fable.wikia.com/wiki/Potion_of_Transmogrification
4. Shaw, A. (October 16, 2013). The lost queer potential of Fable. Retrieved from http://culturedigitally.org/2013/10/the-lost-queer-potential-of-fable