well ive never been in a poly relationship, ive never been in a "open" relationship but i can give views on how i see certain aspects of these relationship.

i dont think its cheating its terms are agreed upon before something happens, i dont think its cheating if there's no sexual contact, nor do i think its cheating if these terms are agreed upon and then someone makes a slight mistake.
what i do think is cheating would be...the two parties not talking and discussing how they feel, what they want to come out of being with others, whats the purpose of them having more then one partner. Some ppl like me, likes to be shared, but i dont like i dont like to share...(im weird that way)...i also have a jealous bone but if there's no sexual contact i can deal with it...

i say cheating or just wanting to play depends on the ppl involved...some may take kissing as cheating while others may take finger a cunt isnt cheating, it just depends....i would say to work it out, talk and see how u want things to work out, be open and honest with the person your with and remember to have safe fun!