When two people are seen making out in a public area like a shopping mall or a park. Usually said when the two people can't keep their hands off each other and are constantly kissing each other.
PTD (post-Tour depression) is a common pathological ailment amongst young British students that are in a state of mental and physical recovery after a frivolous week of self-debauchery and entertainment. It is common and needs to be addressed by further alcohol consumption, extended periods of sleep or repeated crying.