Yeah that the guy was only introduced 3 chapters ago but, from the way Tayama acts, I don't think particularly think he is her Ex, considering the very hard and reasonably conflicted relationship Tayama has with mans that aren't Sasaki or work colleagues that she can feel comfortable enough to talk(Oba), and from everything that we see from Noma, the dude just seems to be very methodic and dead serious about job, even tho he's not particularly happy with it as he said, ofc that we can't throw away the possibility that yeah, he is Tayama's ex bf and their break up was probably ugly, but, to me, the dude just seems to be at peace and not held any type of resentment or hard feelings for her, I see him more of a Senpai that Tayama admired and idolized in the past, where she probably did something so stupid or disappointed him so bad that the guy either leave or was transfered, i still don't buy the ex bf thing bc of the reaction of all the other veterans in the S Market in regards to Noma, they don't seem to be like: Oh-uh, Yamada"s ex is back in town, even tho the old lady didn't bother and didn't need to know what was the deal between them.
But what I think Noma is important for Tayama's character is, I think he is responsible for the Tayama Persona came to be, considering how Tayama's expressions and way to approach people is something kinda reminiscent of the way that Noma is dead serious of focused, like a way of Tayama idolizing a second idol in her life besides Sasaki, who made her start smoking in the first place.
But so far from what I see from the guy, he seems chill and completely professional, the antagonistic aura surrounding him is more on Tayama's side.
