Just sits down at a table where a person is reading and starts talking at them? Weird.

That situation NTA. The only appropriate thing to ask is "Is that book any good/author good?" or "Umm there's a spider on your shoulder/similar thing people would like pointed out"

He's literally following me at this point as I'm ignoring him and trying to play. When I see it, a city bus approaching.

Nothing say creepy like stalking you. NTA there as well

Yeah you might be a bit 'hostile' but when stranger hassle me when I'm trying to do other shit I get hostile to when it's obvious they just want to shag me. The second you would've been the ass hole if he wasn't being an arrogant stalker twat, because that is a more socially acceptable time to try and ask someone out, since hobbies are social. But who the fuck tries to pick up someone reading a book? That is 100% NTA.