The term 'hard-to-please sort' can be described by two crossword solutions: 'FUSSPOT' (7 letters) and 'GROUCH' (6 letters). FUSSPOT is a noun that refers to a person who is very particular and difficult to please. It is derived from the verb 'FUSS, ' which means to worry or complain about something. GROUCH, on the other hand, is a noun that describes a person who is habitually irritable and bad-tempered. Both words are used to describe someone who is hard to please and often complains.