J-Virus
J-Syndrome is when someone in your group disappears with a stupid excuse and then shows up later like they were never gone, but still want to be part of the fun.
Left the party to 'look for a lost dog' and came back to say they wanted to eat the last cake.
Exited the group chat to 'do a quick task' and came back to complain about the music.
Dropped out of the hangout to 'get a snack' and showed up later to ask why no one told them about the surprise.