Possible Clues:

• A client is surprisingly stiff
• Firm, not springy
• Lacking spring clean, it is messy
• It's stiff and one cleans it with difficulty
• Firm's client is a drunk
• Appearing upset, since tail's stiff
• Not reforming after doing a stretch
• A client is difficult and not flexible
• It is clean in action though lacking resilience
• Rigid