I thought this episode felt very out of place so late in the season, it feels like something that should have happened much earlier, not within the last 10 episodes.
I really disliked how the entire team seemed utterly incompetent in catching a single thief. If she had some kind of special abilities, it might have made some sense and I could have overlooked if she was against just one of them, maybe Hiromu could have "underestimated" her, but she manages to out fight and escape from all 3 of them? :redface2:
I also disliked how little power they seemed to have when it came to recovering one of the cards. I don't think Japan law operates by "finders keepers" and when it comes to something which is a massive threat to national/world security, you'd think they could just take the damn thing, or at least have something of value to offer him in exchange.
I did quite like the Pink Buster character herself though and the episode did make me wish we had a character like this join the team (if only to have more girls). I know it's a rather played out archtype, but having an ex-thief type character who wanted to complete a lot of their missions by less savoury means would have been a more interesting dynamic than anything we actually have in the show.
TL;DR: Another disappointing episode from a disappointing season.