Xia Xinfeng, from Maolou in the central province of Henan, passed a capsule with rat poison from her mouth to her long-time lover Mao Ansheng during a kiss the Shanghai Daily said.
Mao swallowed the capsule and died.
“The couple had said that if either one of them cheated on the other, he or she would have to die,” the paper said in explaining the mouth-to-mouth assault.
Xia found Mao had been “talking” with another woman and deemed that he had broken their promise.
Rat poison is one of the commonest methods of murder and suicide in China, so much so that one variety, dushuqiang, was banned three years ago.
In one case, a widow used it to kill 10 guests, with whom she had been engaged in a feud, at her husband’s funeral banquet.
Despite the crackdown, however, besides Xin Xinfeng, a couple from Yunnan province were also sentenced to death this week, suspended for two years, for lacing their respective spouses’ dinners with rat poison.