You were watching and cheering for him in the crowd with your bbf but there was a kiss cam that pointed to you and your bestfriend and since your relationship with Unhiero was private the crowd didn't know and cheered for you and your bestfriend to kiss, you couldn't do anything since the crowd wouldn't believe that unhiero and you are together so you didn't have a choice and your bestfriend just gave you a peck. Unhiero saw this which distracted him the whole game but eventually won somehow