Portrayed by: Machigerita
- "I have no face, therefor I do not laugh, nor do I cry"
A literary master born in the Meiji era. We are introduced to him in A Certain Man's Lifetime and see the events that lead up to his death. He was born dirt poor and wanted nothing more than to become a famed author, so when he was old enough he moved to Tokyo to study in a mansion. While there he met and fell in love with the mansion owner's daughter but due to the diffrence in their social status he couldn't be with her. Over the time he studied he resolved to court her when he had gained the fame he sought after, but before he could even confess, she got married to someone else and left the mansion. Though broken hearted Agate kept studying and eventually was discovered by a publisher. After becoming famous, he met his love once again and saw that she was happy with her husband. Though he tried to keep working, he simply couldn't live with the fact that she had rejected him and took his own life. In the end, nothing of him is left, a left behind candle sets his house, work, and body ablaze.
- Big Sleep: Fin describes him as "sleeping" in his room after he dies.
- Bishounen: As expected of someone who is portrayed by Machigerita.
- Driven to Suicide: Despite becoming a renowed author and gaining the fame he sought after, becoming rejected by the woman he loved still hit him hard.
- Interclass Friendship: Was on friendly terms with a rich woman, although he wished there was more than that.
- Rags to Riches: Went from poor nobody to famous author. Too bad it didn't last that long.
- Laughing Mad: Towards the end of his life. Most likely because of his exhaustion and depression.
- Self-Immolation: It's uncertain whether it was inteded by him or not, but after his suicide by sleeping pills a candle he neglected to put out burned his entire house down, reducing his corpse to ashes and leaving the occational small paper piece of his works left.
- Straw Nihilist: All he goes on about in A Certain Man's Lifetime is that he can't feel anything and wants to die.
Mansion Owner's daughter
A rich man's daughter and the object of Agate's affections. Unfortunately she did not return his feelings and married a rich man instead of him.
- Happily Married: To her husband. Whether it was a man she loved from the start or a man her father chose or both is uncertain, but she is still happy with him.
- Interclass Friendship: Was at the very least on friendly terms with the poor Agate Chirimu.
- No Name Given: Despite her importance to the story, she isn't named.
- Oblivious to Love: Never realized that Agate loved her, and he died before he could tell her.
- Ojou: The daughter of a rich japanese man.
- Satellite Love Interest: We don't know much about her other than that Agate had unrequited feelings for her.
- Unwitting Instigator of Doom: Reuniting with Agate after she married another man sent him into depression and eventually resulted in his suicide and the desruction of his work. Most likely she just wanted to reunite with an old friend and didn't expect him to react like that.
- Uptown Girl: Unrequited version. Agate loved her but she didn't love him.