Anime where (I think) a government agency is trying to catch a real life killer via the internet.
The killer is offing the users behind very popular internet personas/avatars and then taking their avatars and upkeeping them (or tanking their reputations to keep people from questioning why they’ve become inactive).
The good guys use the internet and personas/avatars to investigate the situation. One avatar they talk to in their investigation was a white/grey, kind of emo/dark lolita cat that came out of a haunted looking house on a spring like a cuckoo clock. I think the killer might’ve taken this avatar at some point too, if not while the good guys are speaking with it.
I can’t remember if the killer is caught before he kills himself, but I think it’s ultimately revealed that there’s a more sinister group operating behind him.
The online scenes are operated very similarly to Summer Wars, but I’m almost certain that it’s not Summer Wars.
This could also be a movie, but I just can’t remember. I can’t remember when it came out either.