This is not really what you're looking for, since Lisa doesn't feature in it that much, but Better Than One (http://maychorian.livejournal.com/242718.html) is a good read. It's more of a Dean and Cas bonding gen fic, but it does start at Lisa's house and ends with Dean going back to her.

Summary: Castiel and Dean both need a "vacation from normalcy." It's a post-apocalyptic road trip with grieving Dean, concerned Castiel, monsters, diner food, crazy motels, and historic downtown districts. No Sam, but he is very much on their minds.

It may not be exactly what I requested but it sounds really interesting. I'm always a sucker for a good Cas/Dean fic in any form or fashion anyway.

Thanks!

I actually just finished one a few days ago that had Dean and Lisa ending up together for life!

It will be up in a few days.

Oooh~That sounds intriguing. Could you post a link here when you get it up? Or let me know what community you planning on posting it or are you just goint to put it on your journal?

Can't wait!

It'll just be on my regular journal -- keep an eye out for "Unexpected Landing".

If self-recs are OK,I have a couple.
Sour Cherry Pie Life, crossover with Criminal Minds
http://faithburke.livejournal.com/50588.html

Role Model, crossover with Leverage
http://faithburke.livejournal.com/39773.html

Looking Through Windows
http://faithburke.livejournal.com/57491.html#cutid1

I love Leverage and Criminal Minds! Self-recs are definitely welcome. :)

Thank you so much!!

Going back through the threesome tag and thought, "Ooh, I think I have some Dean/Cas/Lisa fics in my memories!" Hope they're still up your alley. :)

Impressionist (http://cupidsbow.livejournal.com/414272.html) (PG-13; spoilers through mid-season six)

Telegraph (http://chocolate-muse.livejournal.com/35420.html) (adult)

Oh wow! It's been a while, but yeah-definitely still interested :).

Thanks so much!