Possible Clues:

• Devotee beyond reason
• Monomaniac
• Buff device that cools garret, it's said
• Cooler part of house, say, for extreme enthusiast
• Cool off by upper room reportedly in buff?
• Funny at first, prank involves a zealot
• Person who is frantically or excessively enthusiastic
• Zealot in cooler upstairs room losing heart
• Major enthusiast
• Overkeen supporter in fact heading for Arsenal ground