Can certain cards indicate that your new flame is er, spreading the fire? Yup. There are cheating cards. Let's take a look:
Lovers is often a card of a love affair, but it also infers a clandestine affair … torn between two lovers. So if Lovers shows up in a romance question, either look for another lover in the spread, or look for other 'cheating' cards.
The imagery says it all. If you have a Rider-Waite type deck, it usually shows a dude sneaking over a wall with a stash of hot booty tucked under his arm. This is the card of a sneak or thief, so if you're asking about LUV and this Bad Boy shows up, someone is cheating..
This is a card of grief & betrayal. So if this card shows up with another “cheating” card, someone may be nursing an achy-breaky heart soon..
The moon is about what goes on in the shadows, about hidden enemies & represents women.
Hmmmm.... so if this card shows up in your reading around a guy you have the hots for, he probably has the hots for more than just you or there's another woman he's keeping hidden from you. Because the Moon indicates hidden enemies, the other woman/men in question may actually know about you &could even be sabotaging the relationship. Depends on what other cards show up, tho.
The Slut Boy card! This guy can't keep his Little Man in his pants, ya know? But he's very charming, and can be up front about being in it for a good time not a long time. Generally the difference between the 7 Swords & the Knight of Wands, is that with 7 Swords, dude/dudette is cheating, skulking, lying, etc, whereas Knight of Wands is often someone who's sowing his/her (many) wild oats. If he's cheating, he'll be the type to grin cockily (forgive the pun!), shrug & say, “Hey, whaddya expect, I'm a guy!”