Modifiers matching grump:

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

Simple categories matching misanthropic:

• writer,
• businessman,
• criminal,
• person,
• politician,
• grump,
• malcontent,
• miser,
• traitor,
• professor,
• doctor,
• campaigner,
• scientist,
• vigilante,
• novelist,
• intellectual,
• detective,
• tyrant,
• caveman,
• scholar,
• historian,
• bully,
• robot,
• journalist,
• snob,