Pranky Little Krishna

One day Baby Krishna was playing with Baby Radha. As usual Shri Krishna was defeated. Yet He was not ready to pay the wager of the game. Instead He tried to flee. Shri Radha caught Him by the arm and commented, "Where are You running away. Pay the wager". He tried hard to set Himself free of Her grip. When He could not free Himself, He started crying like an obstinate child.
Seeing that Radha Rani let Him go and told Him to not come and play with them ever again. Krishna went home and feeling bad about having lost to Radha Rani, he wanted to gain Maiya's sympathy. So, He lied to Maiya saying, “a girl beat me up". Next day, Krishna requested Baby Radha and her friends to let Him join their game.

Shri Radha being ever so kind and gracious allowed him to play with her and her sakhis, on the condition that He promise to pay the wager on His defeat. He promised and asked what would be the condition? Radha: “You always refrain from paying the wager. Hence, you decide what the wager should be and stick to that”.
So skillfully Shri Krishna played a trick. He said, "Who so ever loses will have to pay the wager immediately. If I lose, I will have to marry You and if You lose, You will have to marry Me". Innocent Radha Rani could not understand the trick of pranky Krishna.
She clapped since Shri Krishna always lost to Her and he would have to pay the wager. She rationalized it as "this time when He loses, He has to marry Me, I don't have to marry Him". Thinking thus Shri Radha agreed to play for this wager. Kripalu Ji Maharaj says, "Shyamsundar, in His mind, is extremely pleased with His frolic".
From Prem Ras Madira (Shri Krishna Baal Leela)