Max-imum Embarrassment With Little Bro Ash (Private with Anon7921)
 

Max defeated all 10 challengers of the day for his gym. He was just about to close the gym as he spotted a familiar face. That face was of Ash. He finally returned to battle him, just as he promised. Max rejoiced at seeing the familiar friend. If only he knew what would become of Ash....

Ash smiled as he saw Max and said to him, "Ready to hand me a badge?" Not really thinking much of Max's skill just yet...

Timeskip to the end of the battle. (Want his diaper secret to be revealed?)
I won Ash.

(Yup)

Ash was still stunned at the fact that he had lost and just stammered, "H-how?"

( Just let me know when you are ready for Eevee.) I have better Pokemon and better skills. Now tell me Ash what is your deepest secret? About Pokemon Battles of Course.

Ash blushed red as he had to fulfill the penalty but was so embarrassed about this that the sound of wetting soon sounded throughout the gym...

Did some little baby wet himself? Max asked clearly.

Ash whined as he heard that and looked down at the floor as he soon finished wetting himself

Do you need a changing Ash-Ash?

Ash blushed before he said, "Y-yes, I do"