|Alter Ego||Arsène (アルセーヌ)|
|Occupation|| Student Council President|
Phantom Thief Leader
|Group(s)||Gentlemen Thief Empire|
|Toy||Toys of Resplendence|
|First Appearance'||Moving into the Attic|
|Voice Actor||Satomi Akesaka|
Henriette is a caring woman that worries about the students of Holmes Detective Academy above all else. She's also severe and will do everything she can so the students end up being great Detectives that will be able to fight the strongest Gentlemen Thieves. Her greater hopes in this regard are Milky Holmes, but since they lost their Toys, they seem to have given up, so she puts them ultimatums so they start working hard again, remembering the pride of being a Detective.
Arsène's main trait is her pride. Not only she has pride in stealing and her way of doing it, but also in overcoming the hardships she finds while doing it. The only ones that have proven to be able to stop her are Milky Holmes, and she considers them her rivals. Her greater joy is fighting them. She's a woman that loves beauty, and therefore her crimes must be beautiful. She considers mysteries and enigmas beautiful and those who kill and cause unnecessary destruction unworthy of the name of Gentleman Thief.