Dear 100 Hour Board,
Short story! I was using Mutual and I found a beautiful girl that I am very interested in getting to know and asking out. I sent her a Note. However, I recognize that it's possible that she doesn't actually use Mutual. Also I found her on Facebook. In a few weeks, do I send her a casual message on Facebook just in case? Too weird? Or worth it because what do I have to lose?
-Hmm maybe I'm more desperate than I think
That's not a great idea. She was using Mutual, which is a way to mediate these kinds of interactions, and if she's not using Mutual, it's likely she's not open to that kind of interaction. I would say it's best not to, and like the other writers have said, if you see her around, great. Go ahead and talk to her instead of possibly risking a weird interaction that she isn't looking for right now.
Keep it real,
I think maybe not worth it. If you were just dealing with personal embarrassment it would totally be worth it because who cares? But you're also dealing with the peace of mind of another human being. I would be a little unsettled if someone approached me in that way. I think it is kinder not to. But I get why it's tempting for sure. There's always that split second when an attractive stranger is walking the other way and you think "Dangit. I'll never see them again. Should have said something." But the thing is you totally will! You won't see that person specifically, but you will see someone you think the exact same thing about. Beautiful people are everywhere and there are lots of them you can approach in more comfortable ways.
Definitely don't do that. Dating via apps can already be kind of nerve-wracking, because it's hard to get to know someone you haven't met in person. Showing too much enthusiasm or interest might communicate a weird vibe to this girl when you don't know much about her other than that she's beautiful.
If you ever happen to meet her in person, then you can ask her out. Otherwise, unfortunately you might have to let this one go.
P.S. I may be biased because a guy I met on Tinder and went on one date with messaged me last night and said he was scared I was going to meet someone else, and that's way too intense for someone I've spent less than two hours with.