There were 2 stories I read a bit ago both in the same universe. The first one had Rumble mentally becoming more and more feminine due to Zecora needing some feminine stallion semen at which point he turned back to normal. The second one had Soarin slowly mentally regressing due to Zecora needing semen but from an innocent stallion I believe. In that one Soarin chose to stay mentally regressed I believe because he found it easier to cope than to what he though live forever incontinent. I’ve looked in here to no avail and my meger ways of checking on FimFetch have also proved fruitless. Does anybody have a link to where these stories are?

https://www.fimfiction.net/story/486358/a-new-view-of-you both are probably from same author.

hmm interesting