Possible Clues:

• Grown grub
• Your setter's past being fully adult!
• My light is green - that's perfect for the insect
• On reflection monogamist enjoys a perfect state
• Adult bug
• For example, monarch ultimately is villain, grabbing maiden
• Love match mainly before I upset spinner, say
• Compiler's past final stage of development
• Insect in its adult stage
• Mental picture of him, a god