Recommended Relics: Ice-Breaking Greatsword, Soul-Shattering Sword (Only use the latter two if you have a fast denier that can Freeze, Stun, or Possess) Counters Whale Hunter / Star Killer / Shikake Waza.Renzuko Waza (Bleed + Sunburn + Self Extra Turn, 13s, 3 CD).Star Killer is plain better than Whale Hunter due to having a higher power at 65 dmg and a more damaging Torture effect (Sunburn), though Whale Hunter is better against Water monsters.
But either Star Killer or Whale Hunter are usually more preferred for the sake of having a damaging move that has no cooldown.
For the final skill, Fear No Dark can be used for making your attacks more accurate with Precision. Shikake Waza is an extra turn skill to deal raw damage. Deadly Haiku has a unique AoE Sunburn + Bleed, which even most Light Legendaries don't have. Be Water is basically Angry Xenophagus ( Ixofex) or The Magnificent ( Greedy Dragon) on steroids, and those two skills are owned by Legendaries - that being mainly used for the instant Damage Boost. This set is the most preferred to make use of Kaori's outstanding attack stat.