Same way he won a Porygon when trying to buy a Vulpix; Lady Luck's got a thing for brave idiots and she isn't shy with a kiss of fortune for yours truly.
"Naaah, I'll be fine! I got my Pokemon to look after me!" He paused. "...The sensible ones. But some of the tricksters have my back too."

An Tintreach grinned, turning - she couldn't leave Kitty out! She began to run at her, darting back and forth in a zigzag as she charged at her.