KOYA
Koya's journey is a spiritual one. I plan to have her character arc advance the philosophy that all things have a sacred nature, and that every place, creature, and object in the world should be honored for the part it plays in the larger whole. Koya displays the ability to find beauty in the harshest environments and to take joy in life to the very end.
Koya's subplot will mostly advance through conversation and role-playing.
"The Brinewall Legacy": I plan to add a beautiful illustrated copy of the Tayagama to the treasure of the Kaijitsu's Blossom. Koya will take an immediate interest in the manuscript, and giving it to her will improve her relationship score by +1. However, damage to the book makes translation difficult, and Koya will find that even using her comprehend languages spell, she is left with the nagging feeling that she is missing some nuances of meaning. She will ask the PCs for their perspective, sharing the plot of the book with any PC willing to listen (or encouraging them to read it themselves if they have the ability).
After describing the book, Koya will share that she is troubled by the nature of the oni. The Tayagama seems to indicate that it is their materialistic passions and desires that corrupt them to evil. However, the material world is sacred to Desna, and Koya does not believe that passion is sinful. She asks the PCs for their opinions on the subject, listens thoughtfully to their answers, and then offers a Harrow card reading to any PC who considered the subject respectfully (regardless of their conclusions).
In general, for PCs who express mistrust of material things, Koya says the cards indicate they are guided by higher purpose, but she warns that they must remain compassionate towards those who follow different paths. The next time they fail a Will save, these PCs will gain the opportunity to immediately re-roll the save.
For PCs who embrace the material world (or reject the notion of spirit/matter dualism), Koya says the cards mark them as favored of Desna, but also warn of danger and temptation. The next time they fail a Fortitude save, these PCs will gain the opportunity to immediately re-roll the save.
"Night of Frozen Shadows": If the PCs recover and ally with Helgarval, Koya will take an immediate and abiding interest in the angel. If the PCs allow her regular access to the helm, she will develop a habit of settling in for lengthy discussions and debates with Helgarval over a cup of tea. (The angel does not drink, but despite its lack of apparent sensory organs, it claims to enjoy the scent of the tea and the sight of steam curling from the cup.)
Over the course of these conversations, Koya's initial sense of awe quickly evolves into an irreverent affection for the angel, which in turn seems to mimic her patterns of speech. Soon the two are going back and forth like old friends: "Now see here, you old tin can, that might true in Elysium but here in the real world things are mighty different!" To which Helgarval snaps back "Old, yes, and where's your respect for your elders, whippersnapper?"--prompting a delighted chortle from Koya.
At some point during a lull in the action, Koya will invite the PCs to take tea with herself and Helgarval, and "settle a dispute." It comes out that the two have been debating the nature of free will. Koya believes in freedom rather than destiny, and holds that until the moment of death all creatures retain the possibility of change. "You can never know which lowly worm will transform to Desna's butterfly," she says. But Helgarval responds that all things have no choice but to be what they are--Desna's freedom is the freedom of self-expression, but destiny cannot be denied. "Time is an illusion," the angel says, "and the caterpillar and the butterfly were always one."
Again, Koya asks the PCs for their perspective, and once more listens thoughtfully regardless of how they respond. PCs who participate in the debate gain a +2 to their relationship score with Koya no matter which side they endorse. When they have shared their views, she drains her cup of tea and invites them to do the same, offering to read the leaves that remain at the bottom of their cups.
For PCs who express a belief in free will, Koya says the tea leaves speak of allies in unexpected places. The next time they are asked to make a Diplomacy check, these PCs may proceed as if they had rolled a natural 20.
For PCs who express a belief in destiny, Koya says the auguries tell of hidden enemies brought to light. The next time they are asked to make a Perception check, these PCs may proceed as if they had rolled a natural 20.
"The Hungry Storm": Earlier in this thread others suggested giving more foreshadowing of Katiyana's return. I plan to do that through Koya--after Katiyana is defeated at the Storm Tower, Koya will grow withdrawn, scanning the skies with a worried expression and repeatedly shuffling and laying out her Harrow cards as the caravan continues. Sometime before the undead show up at Dead Man's Dome, Koya will take the PCs aside to tell them her auguries tell of a coming storm and an enemy "more powerful in death than she was in life."
After Katiyana is destroyed, Koya will ask the PCs to participate with her in a ritual to reconsecrate the Uqtaal Necropolis, which gives a bonus to her Relationship Score as detailed in the module. At the conclusion of the ritual, Koya will again become pensive. Finally she will admit to the PCs that while she is revulsed by the destruction Katiyana caused, she could not help but admire the power and beauty of the storm. She confides to the PCs that she has taken a great deal of joy in their trek across the Crown of the World--tasting new foods, speaking to new people, seeing amazing sights with her own eyes. But she has also witnessed suffering and evil, and she wonders if it is selfish of her to take pleasure in the world while others remain in so much pain.
So long as the PCs respond respectfully, they will earn an additional +3 to their Relationship Scores with Koya no matter how they answer. (PCs pursuing an enmity relationship with Koya may earn points by mocking her instead.) However, some weeks later, Koya will return to the subject. To PCs who generally endorsed finding joy and beauty in the world despite the presence of pain and evil, she will tell them that she has decided they are right. To PCs who endorse any other view--such as the notion that pleasure is fleeting and virtue lies in self-denial--she will tell them that their way may be right for them, but she has decided it is not right for her. To thank them for helping her along the journey, she has crafted a magic item for each PC tailored to their class and abilities and incorporating materials harvested from the significant enemies they have defeated so far (such as dragon's claws or yeti pelts). (I plan to give Koya additional crafting feats as she levels up, but she can make the PCs a gift of potions at the very least.)
"Forest of Spirits": Koya is delighted and fascinated by the kami, who to her embody the link between the material and spiritual worlds. She does her best to befriend Miyaro, and is pleased with the PCs if they recruit the kitsune and are generally friendly to the kami. She is very interested in exploring the House of Withered Blossoms. I intend to use her interest as a way of guiding the PCs to discover the various pieces of information they need to gather there (using her fortune-telling as a guide if necessary). If the PCs give her time to peruse the oni library, not only will her Relationship Score improve as detailed in the module, but I will probably allow her to discover the important secret that not all of Anamurumon's descendents were destroyed: one grandson was deemed promising enough to live, although Anamurumon did kill the boy's mother in order to ensure that his loyalties were not divided.
In general, I plan to portray "Forest of Spirits" as a sort of culmination of Koya's spiritual journey. Meeting the kami brings her an enormous sense of personal fulfillment. She feels the journey was tremendously worthwhile and that it has brought her a far deeper understanding of the world and her own place in it. After the events in the House of Withered Blossoms, Koya remains an enthusiastic ally, but she is no longer driven by a sense of restlessness and missed opportunities. Instead she simply looks forward to each day and each new opportunity as it comes.
"Tide of Honor": In this module, I'm concerned that the riddle of O-Sayumi's inro will mean nothing to my players. Koya and her divination magic can serve to guide the PCs as they attempt to decipher the various clues that O-Sayumi has left them.
In addition, provided the PCs introduce Koya to Numataro-Sama, she will obtain permission from the kappa to spend a few days working beneath his sacred magnolia tree. During this time she will "upgrade" the items she made for each PC, infusing them with new powers appropriate to the PCs' advanced level.
"The Empty Throne": Koya may be helpful to the PCs in discovering the various secrets that they can use to destroy the Teamwork Scores of the Jade Regent and his allies.
At the conclusion of the campaign, assuming that Ameiko has been installed as Empress, Koya will announce her intention to return to the Forest of Lost Spirits. She would like to spend more time with the kami, ensuring that the House of Withered Blossoms remains a locus of good rather than evil, and helping the spirits of the forest find rest.
If she has grown particularly close to any PCs, Koya will invite them to accompany her, perhaps even suggesting that the House of Withered Blossoms could become a site of pilgrimage or learning for those who wish to study under the PCs. In time the site could be transformed into a famous monastery, temple, or academy, spreading wisdom throughout the land.