It's most likely a Homer (Homing pigeon) or a cross. The breed you get doesn't matter to it, but get one that is similarly non-ornamentated......pigeons are easy, but the less fancy ones will usually bring even less potential problems with them.
Actually, whether male or female, when alone like...
You should.......start keeping pigeons! lol
Good looking bird, though. Is his beak fine? Seems tame, too, gotta love that.
The two most probable possibilities would be the auction, or someone flying birds and he got lost.
I see a male, lol, but it really is hard to tell with pigeons, especially...