Hi, welcome to the site 

You're a children's book editor. Where's the gap??
He asked for your number. He'll remember you.
Eh, a lot of people have what they would call "many friends". How many of them are quality relationships? You never know what can happen if you meet up. You could wind up really clicking. If that happens, it's not going to matter how many friends he has. He'd make room for you.
OK, just don't let it happen again!!!