Cheaters come in all shapes and sizes – the first thing we all think of is, of course, the kind of jerk who goes behind their partner's back with someone on the side.
And now science has confirmed that once a cheater, always a cheater.
A new study followed 484 people in romantic relationships and asked them whether they'd ever been unfaithful to a partner. Then, it asked whether they'd been unfaithful to the current partner.
The results clearly showed that people who had played away in the past were a staggering three times more likely to do so again when compared with those who reported no infidelity at all.
Luckily, if you're an optimist, that does mean that quite a few who'd cheated previously had either got it out of their systems or had finally met the right person.
Published in science journal the Archives of Sexual Behaviour, the study indicates that the old cliché is true: once a cheater, always a cheater.