Modifiers matching grump:

• covetous,
• arrogant,
• rich,
• grouchy,
• fastidious,
• heartless,
• impatient,
• penny-pinching,
• miserly,
• greedy,
• wealthy,
• jealous,
• ill-tempered,
• mean,
• misanthropic,
• gruff,
• grizzled,
• principled,
• condescending,

Simple categories matching fastidious:

• psychiatrist,
• person,
• gentleman,
• miser,
• snob,
• foreigner,
• businessman,
• detective,
• grump,