2018.
This is a Warrior Cats AU by Acorn-Trees on Deviantart.
Link: https://acorn-trees.deviantart.com/
Title: I'm sorry Hawkfrost.
Time: 6H.
Characters: Mothwing (Yellow tabby cat; belong to Erin Hunter), Hawkfrost (Brown tabby cat; belong to Erin Hunter).
Designs (c) Acorntrees.
Plot: https://www.deviantart.com/art/Forgive-Me-Mothwing-717155957