Kenshi Yonezu - Horse and Deer (馬と鹿)
Then what would you call it?
The title song from Kenshi Yonezu's tenth single, Horse and Deer, and the theme of the TV series No-Side Game.
The title is a reference to the etymology of the word "baka" (idiot): the kanji are literally "horse" and "deer," supposedly implying "someone who can't tell the difference between a horse and a deer."
Original video: https://www.youtube.com/watch?v=ptnYBctoexk