她有病叫难伺候他有病叫幼稚鬼

This has an informal or playful undertone. The first half '她有病叫难伺候' refers humorously to a female who acts spoiled or demanding being characterized by her attitude making it hard to please her, whereas the latter half concerning 'he' depicts similar characteristics but instead labels the male counterpart immature. This username playfully points out stereotypical differences between genders in behavior, specifically referring to their faults being named differently.