It's gay guys. There are more then you might think in Asia. In fact, it's very common. It's just not obvious unless you have been here awhile.
I had something similar happen at Lumphini Park in Bangkok. I was sitting at a marble monument near the lake trees, nobody else around, Some Thai guy came up on me, sat close and said "I like gay", that sort of thing. When I told him I was not interested he would not leave or go away, maybe took it as interest, or an interested decline.
I got up and left the area. I don't care about being approached much, but something about him refusing to move on after I indicated disinterest really irritated me and I felt like hitting him. I still remember that stupid smile he had.