Like I said, this is probably really creepy rather than cute. It depends how long the two have known each other. If it was something like proposing, no doubt that would be adorable, but I feel like the guy put way too much effort into this. Did he use the Name Rater, or did he literally train these Pokemon to fight the Elite Four (look at their levels!). Bonus loser points if he insisted on not being around when she saw the message rather than be face-to-face... it would be the same as asking her out via text message when the two had never texted.
Good luck, but I'm not expecting much out of this.