From the Super Mario Wiki
Max Milliplatt is a character that appears in the Club Nintendo comic "Super Mario: Coole Klänge". He is the boss of the record company Koopa Records and signs Mario on, despite the fact that Mario obviously is not a good singer. When he flops, Milliplatt tries to put Mario in a different outfit, without success. Milliplatt seems to be the stereotype of a big record company boss who does not care about the artist but just about earning money. He has a secretary called Mona and is angry with her when she does not manage to stop Mario from entering Milliplatt's office.