Alright so, this has been bothering me for a few months now, and I'm at my limit.

So there's this manga - not sure if it's a series, a oneshot or not even a manga? but I remember quite a few things about it.

firstly, there's a younger character on roller blades, beating people to death. I'm about 90% sure this character is a girl. turns out that this character has a normal life and is a generally shy person outside of the murder-tastic vigilante work. this guy ends up figuring this out and it starts from there? I remember a really cute moment with an umbrella.

This isn't very helpful I know, but it's driving me up the wall trying to figure out what this is! I'll know it when I see it, I know that much! Also, no, it's not paranoia agent - I've never seen it, and in so far as I know, it doesn't have a manga. plus nobody actually dies in that from what I've heard?

Anyways, any help is appreciated!