i rem !
that boy is Dieter (he dont stick 24/7 with Dr Tenma, the main character though), 1 of the patient name is Johann

wont reveal much in case you re-watch but personally find it interestin because along the way they travelled all around Germany (i get to learn of alot of cities, places in Germany

), and Czech and met alot of stuffs and people
just a suggestion la.. i dont watch much anime