Jiro Nezu is an energetic, aggressive, and hot-tempered boy who is surely almost equal to Nero in terms of activity. His fiery hotblooded attitude brings out the offensive in the The Gentlemen Thief Empire during heists.
In Holmes Detective Academy under the disguise as Jiro Nezu, a classmate of the Milky Holmes girls. Throughout the anime, he seems to be cold and unmerciful towards the girls at first blush in school or on the feild. But it is shown that he is actually affectionate and demonstrative towards the girls abeit indirectly, particularly Nero who always seems to be at odds with the boy. A running gag of the series, the Milky Holmes girls never seems to be able to remember his name often calling him something else like Rabbit or Rising Thunder.
Rat's Toy is the ability of pyrokinesis allowing him to control fire which he often used to light various explosives which he uses offensively and defensively.
- Like Twenty, during the first episode of Rats demonstration of his Toy to the Milky Holmes girls never seems to raise any flags that he might be Rats of The Gentlemen Thief Empire.