It’s a brief moment of seduction and meant to turn the Covenant crew-member towards the side of the Prometheus survivor, but it doesn’t work and a big robotic fist fight ensues.
While it’s not exactly a huge moment plot-wise, and it doesn’t take up much screen time, it’s an interesting decision that highlights an inconsistent past with the censors in China.
The moment occurs during the third act of Alien: Covenant, where Michael Fassbender’s dual characters share a kiss, which is initiated by David towards his robot brother as a sign of love.