I would be very, very concerned. Daniel is a very educated and classy person, he would never do that for the sake of キス someone. I'm sure he values 愛 -- and isn't going to randomly go up to someone, and start making out.
If it was just a regular guy, I think my immediate reaction would be "WTF?!" and a 迅速, スウィフト kick to the balls. But since it's Daniel Radcliffe, I might freak out in my mind, but I'd probably just melt in his arms and let him continue what he's doing. :3
I would キッス him back!!! Duuugghhh like who wouldn't? This is Daniel Radcliffe were talking about people!!! Then who knows what happens after were done making out または we just might never stop kissing. lol :) <3