Wow.
This is so wonderful. It reads beautifully. Even your writing style is very romantic. Your sense of place is so grounded, and so well thought out (without being overbearing as settings sometimes get), I felt immediately transported. The level of detail in this is perfect.
I love Sandrine. Girl after my own heart. I'm still a little concerned about Marc and wondering if we'll see more from him, and more of a conflict to come... But I hope not because Marc stinks.
I love Clark's introduction here as well. Somehow you've written him exactly in character, and yet he really seems younger. Full of excitement. I know he has to move on to other places and eventually to Lois and the Daily Planet, but it's a testament to your work that I kinda don't want him to leave.

I want him to stay in Paris and write interesting articles and watch movies with Sandrine and hopefully not get caught (although I'm wondering if it was a specific someone on the roof). Although I wouldn't mind the reveal and Sandrine knowing the secret. She might be a documentarian but I am sure she'd respect his trust still.
Great start!

Will Sandrine find out the truth about Clark? Will this friendship blossom into something more? Will things end on amicable terms? Will Clark one day run into Sandrine again in the future and introduce Lois? (I imagine they'd have a tough time at first, but Lois and Sandrine seem like they'd be fast friends).
Can't wait for more!