Kaitou Reinya

These two anime have a phantom thief girl. Queen, Ai and Rose from Kaitou Joker and Reinya from Kaitou Reinya 

Isn't it obivous? Both are kaitou shows :D! 

Both shows have a similar art style. And are about what might be seen as a "bratty" or somewhat self centred person in both cases. Panty and Stocking being about "Angels" who could care little about others. And Reinya as a master thief. Both seem to have a pet in which they abuse, as well as the general cast, and their exploits are all played up for grandeur. While Kaito, in contrast, on the other hand, is just yet a promotion of an idol in the idol industry, and isn't near so crass. It is filled with the limitations of idol, which are actually surprisingly high for it's source(the industry largely centres around innocence and moe). While Panty & Stocking holds nothing back in terms crass humor and playing the lack of innocence of it's characters on all levels, even taking very forward jabs at the idol industry. Nevertheless, while one is an idol anime, and one is mocking the idol industry, both are very similar anime. read more 

Hetalia and Kaitou Reinya are pretty much twins besides the plot (if there is one for either of them). Hetalia is a 5 minute long anime and Kaitou Reinya is a 3 minute long anime. Both hilarious, fast paced, and random with a unique drawing/animation style. You can't really say no to either.