Both are found, thank you everyone :>
I won’t delete this post in case I’d forget the stories again, lol
1: comic
The comic is about college/university professor who finds a laboring mare and he helps her, but the mare is bitch so he leaves her in some random room.
Found by @Fluffocalypse! Thank you! Link
2: textpost
I’m not sure about all the details, but it was about an owner that had a mare that wanted babies, first he tried to persuade her but then he let her go out to find special friend. The plot twist was that when some people found the fluffy, she was full of imbedded gems and jewellery, in eyes I think, and also some decorations in ‘poopie and special place’
Found by @meganonymous, thanks! Link