ピンクの尻尾 / ピンクのしっぽ [pink no shippo] or 'pink tail' in Japanese.
Final Fantasy IV
Obtain: a very rare drop from Flan Princess
Use: give to tail collector in exchange for Adaman Armor
Description: A pink tail.
Grimoire of the Rift

Buy: - (sell: 1,000 gil)
Use: Ace of Spades, Shield of the Four, Adamant Armor, Lordly Robe, Templar Cloth, Wygar, Ruby Earring
Reward: Rumors Abound x2 (once), Rancher's Request - Red x5 (once), Burning Soul (once)
Type: Skin, Rank: ★★
Description: A mysterious pink tail. High treasured as a token of good luck - which is exactly what you need to come by one of these.
Final Fantasy Tactics S

Buy: - (sell: 200 gil)
Use: ?
Obtain: Federation of Nazan/Black Tail Ward lv30+
Description: An uncommon skin
Category: Item