Modifiers matching grump:

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

Simple categories matching miserly:

• person,
• tyrant,
• businessman,
• emperor,
• billionaire,
• grump,
• king,
• tycoon,
• bully,
• miser,