When they start to sing 'So What' you come out of the backstage while indicating everyone to keep quite.
They obey you because they know you are going to do something worse with Jungkook as your relationship with your boyfriend is public.
You come near him and throw the water on him. He looks at you with a 'Wrong move, babe' look.
You start to run away while laughing from there but he is fast enough to catch you. He catches you easily in a blink of an eye and make you drench in water by pouring it onto you.
Members and the fans laugh at your cute water fight.
By the end of the concert, you two look like you both have taken a shower just now.