Prediction:
Next chapter it starts with him apologizing to her for a mistake he made,
the mistake was he told someone about their relationship.
This isn't a dramatic cheating manga as far as I've seen so no way
hope so @Glenng, Yoriko seems really insecure, I'd be sad with a development where she is cheated on. But Shiotani does not seem like he would cheat on her, and its a cute manga overall
@zergqueen
How else are we gonna have a pointless misunderstanding that pushes the relationship to the brink of collapse?
But I agree, that was a rookie move.
@Glenng
Unfortunately, senpai-san is hella insecure, so she's gonna blow things way outta proportion, and then we'll have to suffer through a 5 chapter reconciliation arc... probably. I hope not, but... probably.
@Tlos
Dense? He was just lured into a girl's home under false pretenses and now she's sprung this question on him out of nowhere. He promised that he'd keep his and Yoriko's relationship a secret from the office, so what else was he supposed to do?
@zergqueen
Nah, that's not smart, in my opinion. Tateyama already saw that he went on a date with Yoriko. If he said he was dating someone, but not who, she would just assume it was her, and it might spread around the office.