Blessed with an unwilling mentor

Kazuma was fiddling around with an item in Wiz's shop before he was suddenly transported to another world. The first person he meets here is also new to this world and also from Japan, his name Subaru Natsuki. Subaru will suffer, but since Kazuma is around he is going to get some pointers on what not to do in another world, but Kazuma won't give out tips when Subaru wants them.