Episode 16 is just one giant tear jerker for Mizuno fans everywhere.
Episodes 14, 15, and 16, in addition to being a Wham Arc, all had their fair share of tear-jerking moments. Most of them did indeed involve either Mizuno or Marino in one form or another.
In Episode 20 we knows the deal Head's apparent right hand man Ryousuke had to go through. It is sad. And the man still helps Head or probably hopes to bring back the brilliant artist he knew after all that.