Possible Clues:

• Comes out at sunset following legend close to the ground
• Wild flower with tag, 'Light of Evening'?
• Post-sunset radiance
• Lingering pleasant feeling
• Fog later dispersed, with some residual light
• Breaking law, forget light lingering in sky
• RAF get confused with owl that may be seen when the sun has set
• Great wolf unexpectedly appearing when sun has set?
• Great fowl demolished giving one a lingering feeling of satisfaction
• The satisfaction of slaying great wolf