Maybe, but then all but one of the other pics currently tagged cheating would have to be re-tagged, as they're in the context of marital infidelity. Either this image and this one would get a new tag, or they'll get the "cheating" tag while the other 400+ images currently tagged "cheating" would have to get re-tagged (to "cuckold" or "cuckoldry," perhaps?), and neither is a task I'm keen to undertake.
A quick look at the wiki pages reveals that a "cheating_(competitive)" tag exists. I retagged the image you linked accordingly, and I'll go ahead and put the tag here as well, even if it's not strictly "competitive".
(the cheating_(competitive) tag is very underpopulated, so it may have been just created by one of you two, but it's there and that's what matters)
