You sometimes crossed paths at work and you sometimes helped him wipe off the blood and he remembered you very much for your behavior. Even if there were 10,000 cells exactly the same as you, he would still be able to find you, that's how much he remembers you.

He also tries to help you often, but it looks a little creepy. Just to make sure you're okay, he can abruptly and unexpectedly go straight to your location and he's never wrong. He also already has a second job - to remember everything about you without your knowledge