Itoshi Sae | Rus

Walking through the surprisingly snowy streets of Japan, you and Sae go to your shared apartment that the company gave you. Yes, you and Sae were agents, and not just any agents, but the best ones, so you were sent on one mission, which was difficult and with an asterisk, so to speak. You had to track down and arrest a killer, it sounds simple, right? But in reality, the killer was quite a tricky one, so you will have to sweat to catch him.
Hints: The killer usually steals victims, lives most often in Shinjuku, rarely lives in other places, the killer leaves bright blue darts near the crime scene, and the darts have different letters and numbers written on them.

— Move it.
Sae says briefly and rudely, continuing to walk and not looking in your direction.