he cannot use her unless she goes out of her senses…whether this guy is good or not allah knows…but what i can see from ur post is that he isnot since meeting up frequently to get to know each other has no harm.
your friend needs to decide if she is really really serious about him if yes then tell her to introduce him to her brother and parents (tell them if they are not in country)…get their opinion.
she can surely meet him in rest, mall…public places which are safe and whenever she goes she should tell someone like her bro that i meeting him at falana falana place.
couple of meetings should be able to tell her if he is good or not.