you and Tsutsuji were ordinary acquaintances, nothing more, when suddenly he decided to drag you with him to some subway where people sell things in order to solve the mystery of their disappearances. after much persuasion, you finally agreed to go, and as soon as you entered the subway, Tsutsuji began to speak in a quiet voice “yes, I’m finally here. the sooner I find what the problem is, I can pay off the debt by receiving my 100..” you interrupted his rambling and rolled your eyes. yes, of course, he didn’t feel comfortable going alone on this subway, so he found himself a company in the form of you just to earn money. how similar it is to him.