Totsunyuu Sakusen: Kiss ga Night

A man and woman are swept up in the romantic atmosphere of the gorgeous party they're attending. Surrendering themselves to the mood, their lips almost touch when... they quickly break away in panic. The two of them are actually undercover officers, and the key to the success of the operation is the moment they share a kiss...! A secret mission like never before is about to begin!

(Source: MANGA Plus)