A couple shocked onlookers as they romped in their hotel room with their window curtains open in China.

Footage shows the exhibitionist pair thrusting in full view of cosplayers attending the Pazhou Firefly Comic Exhibition in Guangzhou, China, on May 3.

Stunned youths watched as the couple had sex against the transparent full-length glass window, with several titillated teens pulling out their phones to record.

The man was seen grabbing his partner's hair like reins before police arrived to arrest them for alleged public indecency.

The scandalous romp was reportedly orchestrated by an adult actress, who goes by the online handle TeaMeowMee. She was said to have been detained by cops for questioning.

Laws in China prohibit public obscenity, which is punishable with fines and imprisonment depending on the nature and extent of the act.