I've been absent from the community for quite a while and now I've started reading all my favourite stories again...and I remember one quite clearly but have no idea where I can find it, so I hope you can help me out :)
It plays after GoF, I think. An older Harry from the future comes to pick up Harry and train him for his future because in his time, that never happened and he lost all dear to him.
It is a HP/SS-Slash story...the future Harry was together with Snape and they even had kids (only mentioned) and in this story, the 5th-year Harry gains a new understanding with the potions master and they also find each other.
Meanwhile, future Harry is also at Hogwarts (but I'm not sure if he took over DADA or not) but also becomes friends with Remus and Sirius (later they even become a threesome, if I remember correctly).
I'd be very grateful for anyone who knows this story and can let me know where to find it.