Possible Clues:

• Unpleasant smell: a new kind
• Like Peter Quill of the Guardians of the Galaxy, in part
• With 58-Across, why we do what we do
• Fallible
• Be very busy with a new person
• With 40-Across, a punny title for this puzzle
• You, for one
• Malnourished missing soldier? Corporal!
• Like you and I
• Most dangerous animal on Earth, many say