I enjoyed testing Pillow Fight Arena! The little characters are cute and I like the colorful style.
A few suggestions: the controls (R, Space, Shift) would be better fixed in a corner instead of following the character. The number of enemies feels good as it increases over time, but they could move a bit faster to make the game more dynamic.
The “You Won” screen could also be better centered or displayed over the whole game screen.
There are still things that could be improved, but I had fun testing it. Keep up the good work!