This is based on opinion. Please don't list it on a work's trope example list.
Tearjerker / Dog & Scissors
Well, the series does start off with the death of the main character...
The little inserts of all of Kazuhito's friends and little sister after his death are appropriately depressing. It may be a comedy about a sadistic author and the kid who saved her, died in the process and was reincarnated as her dog, but to them they had just lost a friend/brother who they'll most likely never see again. Well, unless they suddenly believe he was reincarnated into a dog and he can communicate through Kirihime.
The scene on the bridge with Kirihime and Kazuhito in episode two.