Nope, but as far as I know, Littlepip is a lesbian, but her companions are straight, including the mare she has had a crush on since she was a filly (which was one of the reasons that made her leave the Stable to go looking for her).



She does get into an intimate relationship with another mare later in the story.



That all being said, there seems to be equal amounts of hetero and homosexual pairings throughout Fallout: Equestria, but the original story skirts around going into clop territory, with the exception of the fan-made, author-approved chapter 20.5. Which goes into that territory, but also adds a bit more story (the author references chapter 20.5 lightly in later chapters due to this).