I'm damn glad this exists. Best Severus/Lily fic I've ever read, and I've been craving a great one for years. The plot isn't at a fast pace, but that's the way I like it. It introduces [or re-introduces] quite a bit of intelligent concepts seamlessly.

Characterization is brilliant— it may seem inconsistent, but that's simply 1. Lily's age and 2. Snape's time-travelling. The age gap also doesn't come across as creepy. I agree with someone else's post that Snape is what Harry should have been in terms of power + intelligence, and this fic is a great example. Have always enjoyed Snape-centric fics.

As for the romance, Snape's the one showing restraint and that makes it more realistic. It doesn't intrude or take up space. The development of their romance is well-paced and written wonderfully. There's no pointless sex.

Getting technical, the writing is top-notch. No errors I can see [though I'm very immersed in this, so maybe they're left unnoticed]. Use of sentence structure, etc. is well-done.

So. 5/5. It's everything I want in a Snape/Lily. And, sequels please.

 

Call me tasteless, but after reading this, I'd say 5/5 is what it deserved.

 

I forgot to mention this, but the author posted a few new scenes on her website.
http://debpeters.livejournal.com/11686.html#comments

Not a new chapter by any means, but that should provide some satisfaction.