A tamed Pink Lily is one of the best infusion sources of Chain Bonus Boost II, an enhancement of the Ravager's primary function. Since Chain Bonus II is a Rank 6 Passive ability, apt to be replaced by the likes of Auto-Vigilance (Rank 8),
Resilience +40% (Rank 8), Resist Physical +36% (Rank 7), Auto-Faith (Rank 7) or Resist Elements +30% (Rank 9), it may need to be yellow-locked by infusing a second Pink Lily, if the target monster does not have Chain Bonus I or II. Blue Chocobo, for example, has Chain Bonus Boost already, so merely infusing Pink Lily both gives the Blue Chocobo level II and yellow locks it.
This monster ally comes with a built-in defense against elements that is better than Auto-Shell in the amount of protection (except against the rare enemy Ruin or Saboteur attacks), permanent instead of 30 seconds, and does not take up a Passive ability slot. Unfortunately this also means it cannot be infused.