Kurt had a dog named Blaine who was protective of him and slept in his bed every night. One day Kurt wakes up to find his dog has turned into a human who is a few years older than him and is a dom.
Of course, Burt is wary about having a dom in the house with his sub son but he lets Blaine stay, in his own room of course. But Blaine would still sneak out to sleep in Kurts bed.
Blaine starts going to McKinley and joins the football teams. I don't remember if he joins the Glee Club or not.
I remember Kurt was confused about his feelings for Blaine but Blaine was certain that Kurt was supposed to be his sub/mate. There was a scene where he tried to attack Karofsky for bullying Kurt or something but Puck stopped him, saying that he could only attack someone if he was defending his true sub or something like that.
That's all I remember but I would love to find this again!
This is also my first post so I hope I followed all the rules! I will fix anything if need be.