Koushaku Chouno (蝶野攻爵,
Chōno Kōshaku), better known as Papillon in the series, is a genius student from Kazuki's school and was meant to be heir to the Chono family fortune. However, he is also deathly ill and has had to repeat a year of school due to the amount of time he has needed to spend in the hospital. Upon discovering a 100-year-old research diary from his great-great-grandfather he learned of alchemy and the process of making homunculi, experimenting with various animals first before turning himself into a human-type homunculus, renaming himself "Papillon". However, he's imperfect, as he was forced to use an unfinished homunculus core to recreate himself, he now suffers from the same sickness, but won't die. He began his move by eating every member of his family who couldn't recognize him as Koshaku, but as his brother Jirou, to the point of even killing his own father and brother. To prevent Papillon from eating more people, Kazuki had no choice but to kill him. After his initial defeat at the hands of Kazuki, he teams up with the homunculus Dr. Butterfly, his still-living great-great-grandfather. After the LXE fell, he became a team with Ouka to turn Kazuki back to normal again, in order to duel and kill Kazuki. In the end, he does restore Kazuki to a normal human with the white Kakugane he created himself, and loses the duel. However, Kazuki does not kill him because he already killed him once and thought that he was a good person. He then becomes one of the many urban legends in Japan, nicknamed 'Butterfly Man Papillon', where he is now loved by all of the people in the city, becomes friendly with everyone, and even has a promotion deal with the local fast-food restaurant. Like Kazuki, Papillon was seen with his Buso Renkin at the end of the anime, which can imply that he was allowed to keep his Kakugane.
As Papillon, he is flamboyant and reckless. He appears in public wearing his mask and in revealing or outlandish outfits, apparently oblivious to or possibly enjoying the stares of bystanders. He also slowly loses a thirst to eat human and his wish to burn the world to the ground, slowly becoming something more than a homunculus. After Kazuki was thought to have died by the hands of Victor on the moon, he claims the world is trash without him. He deems Kazuki the only human who is worthy of calling him by his original name as Kazuki believes humans can have power without sacrificing their humanity which is something Chouno is trying to disprove.
His Buso Renkin is Kakugane LXI,
Near-death Happiness (ニアデス・ハピネス,
Niadesu Hapinesu). When activated it appears as black gunpowder that typically takes the form of a pair of butterfly wings on his back. He also can create a number of small butterflies from it that explode on impact and that he can use offensively or create a large butterfly which he can ride on. When all of the butterflies are used up, it takes three days to regenerate. When first activated, Papillon suffers a shock which he seems to enjoy, saying he "forgot the ecstasy of near-death".
Voiced by: Mitsuaki Madono (Japanese), Spike Spencer (English)
Source:
Wikipedia
