A NPC of Nazarick that has not been mentioned in the Light Novels or Web Novels and appears will not likely be mentioned. All other details are unknown about Mondenkinto.
Mondenkinto is described as the kindest of the NPCs of Nazarick alongside Pestonya. 
- ↑ Volume 4 Author Thoughts: By the way, the two titans of kindness are Pestonya and Mondenkinto from the WN, Who is it? Because Mondenkinto-san’s is a masterpiece of a character in the story, it will not be revealed in the book publication.