Caligola (12-41 d.C.), for many reasons, It is considered one of the worst emperors of Roman history.
The list of follies attributed, some invented or exaggerated, but most real and documented, It is endless (you see https://www.pilloledistoria.it/8853/storia-antica/dal-cibo-al-cavallo-alcune-follie-).
Among the many, it is said that once, during a banquet, He broke out suddenly and loudly laughing for no apparent reason, when, one of the guests present asked him the reason for such strange hilarity.
The response of the mayor of Rome was that he was thinking of his death, the diner.
Shortly after the Emperor had killed the man, virtually on a whim (Photo gives: https://adeleviericastellano.blogspot.it).