Related Clues:

• Party to
• Not excluded
• Barge --- (interrupt)
• Krakauer's ''--- Thin Air''
• Well aware of
• Word with "each life" or "thin air"
• Studying closely
• Word of division
• ''--- each life some rain ....''
• Avid about
• Informed about
• Hooked on
• Passionate about
• Nuts about
• Deeply involved with