User blog comment:Hitsuji Mamoru/Servant Creation Room 2 : Guess of the Who/@comment-32599925-20170908002630/@comment-32599925-20170921212229

Not from an actual TM work, but written by a writer of a TM work. If they did the collab, it might bring in stuff from that writer's works... or so I hope. It might not be likely, but that author and Nasu are friends, so it might happen if the company that published the original work lets TM use the character.