Koko wa Ima kara Rinri desu. - Vol. 10 Ch. 52 - Prayer

[NerimaShinjuku]

It would make more sense if sensei asked “did she cheat on you?” to which Takayanagi’s “it might have been the other way around” in reply becomes a much more natural setup to sensei’s “might have?”

 

[ocvampirecreeg]

It would make more sense if sensei asked “did she cheat on you?” to which Takayanagi’s “it might have been the other way around” in reply becomes a much more natural setup to sensei’s “might have?”

That’s not what the original Japanese says.

The original Japanese chapter very clearly shows the professor asking if Takayanagi cheated, at least to me.

Another context clue is Takayanagi being shown to be a neglectful partner in chapter 51 (barely acknowledging his partner when she comes to drop off food for him, only giving her attention when the professor’s package is mentioned), which is likely one of the factors that would have pushed Kikukawa to cheat, if we’re assuming that Kikukawa did in fact cheat.