It was explained. It was just lunch with a previous co-worker.
His arms are to his sides and she is the one touching him. I'm sure the uke jumped to conclusions. Its usually the case in these types of stories. The raws seem to point to that too.
Yes, it's a typical false lead situation bound to inflict confusion and pain. But I think Nicholas Hale has a point in asking why it's not resolved.
Then again, it is Yaoi and if everyone just talked with each other and explained everything properly, three quarters of almost every storyline wouldn't exist I guess
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They still haven't explained the seme cheating. In fact, they seemed to put more emphasis of when the uke cheated, but kinda ignored the fact that the seme cheated first. I find it odd that the uke didn't ask for an explanation and that the seme didn't try to explain it. I hope in the next chapters they will remember about this and not ignore it..