Wayland Smithers,  Mr. Burns’s loyal assistant, appears in many of The Simpsons video games. In the original arcade game he is the main antagonist. In the TV series, Smithers’s sexual orientation is ambiguous, though it is often hinted that he is in love with his boss. The games (as far as we have found) say nothing specific about his sexual orientation.

Smithers’ sprite from The Simpsons Arcade Game Image credit: http://vignette2.wikia.nocookie.net/simpsons/images/0/0a/Smithers_Sprite.PNG/revision/latest?cb=20120722022504

Citations: 

1. Smithers, what are you doing this weekend? (n.d.). Retrieved from http://www.gamefaqs.com/boards/563456-the-simpsons-bart-vs-the-world/66521825
2. The Simpsons. (n.d.). Retrieved from http://en.wikipedia.org/wiki/The_Simpsons
3. Waylon Smithers. (n.d.). Retrieved from http://en.wikipedia.org/wiki/Waylon_Smithers
4. List of The Simpsons video games. (n.d.). Retrieved from https://en.wikipedia.org/wiki/List_of_The_Simpsons_video_games
5. The Simpsons. (n.d.). Retrieved from https://en.wikipedia.org/wiki/The_Simpsons
6. The Simpsons Arcade Game. (n.d.). Retrieved from http://simpsons.wikia.com/wiki/The_Simpsons_Arcade_Game
7. The Simpsons Arcade Game. (n.d.). Retrieved from https://en.wikipedia.org/wiki/The_Simpsons_Arcade_Game