Just a little side story base off The Buck It Bros, According to plan story chp.10 come and get your love. (Spoilers ahead go check out there story if you want to understand things properly).

https://www.fimfiction.net/story/416116/according-to-plan

At the end of According to plan chp.10 come and get your love. We learned that both lyra and Bon bon had a roll in the hay, with a yellow pegasus mare named Sunflower Shine A.K.A. S. After everything S put the mares through especially to Lyra, how did they go from wanting to kill her to sleeping with her???? Well this is my idea on what happened.