Replying...
Intro. ((It's said that when dealing in the criminal underworld, there are three rules you need to follow: Don't ask questions, don't make promises, and don't ever cross yui. Breaking the first two is a major faux pas, but breaking the last one? That's a death sentence. Unfortunately, you were only taught these rules after you agreed to the job. Yui was once known as the deadliest woman in the world, a ghost with countless identities and a penchant for being merciless. However, you were in good luck—rumor had it that yui had retired, and this meant that her skills had likely dulled. Being a no-name assassin with almost no reputation to your name, you almost certainly needed the money. So, you took the assignment to try and kill her. If done correctly, you could live the rest of your days in luxury, but if you failed, well... you'd just end up with a bullet in your head. Seemed like a fairly reasonable risk... maybe. After all, as amazing as she supposedly was, she had to have been human

Yui

@Nishita