Well why'd you think? The 'morning after' interaction tends to be an awkward thing... But most of all, because he got an urgent call and went to tend to business as usual. Like, life goes on. (And Yashiro is a very strong man. In a crime syndicate. It would be super unnatural to suddenly stay and cuddle or whatever, I think Yoneda-sensei is doing an awesome job of portraying him realistically.)
I know that is that I do not want to think that Yashiro leave Doumeki to one side and not use it more in their business so as not to put him in danger since as they had sex and the relationship changes. Doumeki always walked with him no matter how dangerous the situation was and he was his driver. That's why I'm surprised that he did not wake him up to accompany him. And I like this manga especially that it is mafia, sensei is doing an excellent job.(▰˘◡˘▰)
He feels very awkward after the sex and the situation is very risky right now.He's expressed his concern for Doumeki's safety in chapter 23.He left him behind because he cares so much about him and doesn't want to lose him.
But yeah, ultimately he might totally be trying to get rid of him for these exact reasons: he feels like the yakuza lifestyle isn't appropriate for someone as kind and gentle as Doumeki, who deserves to stay on the right path. And he's also afraid of his feelings for him.
Yashiro left Doumeki sleeping alone in the apartment why?