No one can possibly tell you if he'll be be denied or not. You haven't told us anything that would affect that. He's just coming as a tourist, partly to meet an online friend. If he has all the usual stuff that tourists are expected to have, like a return ticket, the correct visa, enough money to look after himself while being a tourist, plans for what he intends to do in your country, and ties to where he lives like a job and a place to live, it shouldn't really matter if he's only met you online. And he shouldn't lie about anything when the immigration people ask him stuff.