If Julianna is chosen as magic mentor, then Selene's role in the story will be minimal, possibly being mentioned in only one scene. If Julianna is rejected one way or another, Selene will take a much more active role.
She hides more than just the priesthood's mysteries.
Spoiler Warning: Plot details follow, read at your own risk
If Elodie had Julianna arrested, Selene will request her freedom. Disagreeing will permanently bar the player from acquiring the Lumen skill, otherwise it will be available later.
If Julianna was sent away, then Selene will reveal her powers and offer to become Elodie's magic tutor. Fail a Lore >10 check to be scolded. If refused, then the Lumen skill will become unavailable for the rest of the playthrough, otherwise you gain a magic tutor.
If Julianna was accepted as magic tutor the Elodie will spot her and Selene at the palace garden. If Elodie hasn't spoken with Julianna in the previous weekends, Selene will advice doing so.
If Selene is your magic mentor, and Elodie hasn't claimed her crystal from the treasury, the former will offer to handle the treasury guards. If refused then she will drop the subject, if accepted the guards will die of a 'mysterious illness' and Joslyn will suspect it being Elodie's doing, +1 Depressed.
If Selene is your magic mentor, the option "Send (the killer) to Selene" is unlocked during the judgement; this option won't need any checks or have negative consequences, but Elodie will miss on the killer's crystal. Choosing to do so also unlocks a Special Weekend Activity.
If Selene is your magic mentor, pass a Foreign Intelligence >100 check to understand how much of a threat your enemy is. Should you've not managed to recruit another Lumen by this point, you have to option to recall Julianna. If you have access to at least three Lumen (counting Elodie herself), then Selene will suggest to sink the invading fleet with magic, but will also be clear on the consequences; you can accept or refuse.
If Selene is you magic mentor, or discovered Selene's status with Julianna as magic mentor, and accepted to execute the magic ritual, she will be present for it.
If Selene is your magic mentor, you gained a spare Lumen crystal (during Week 17 or Week 20), and lost the naval battle, unlock the choice to "Offer him your power". This option can also be unlocked by other means.
If Selene is your magic mentor, lost the naval battle, and refused the magic duel, you will meet with your advisors during the weekend. Selene will suggest a dangerous method to deal with the invaders; if accepted, a special event will take place next week and override the weekly classes.
If you accepted Selene's proposal last week, all classes will be skipped for the week while you prepare to attack the invaders from afar. If Meditation <10, +1 Afraid. Pass a Lumen >240 and Meditation >60 *OR* Lumen >300 and Meditation >10 check to summon a terrible earthquake to kill the enemy commander and his soldiers, but also cause extensive damage in nearby lands and lose -20 Commoner Approval and 4,000 lassi.
If you executed the magic ritual during Week 35, a kraken will be rampaging through the novan coast. If Selene's status as a Lumen is revealed, she will present you with two choices: seal the kraken with a costly and time-consuming ritual or sacrifice a young Lumen. Unlike Julianna she will be brutally honest about the choices and their consequences.
Special Weekend Activities Edit
After Week 6 Edit
If Selene is tutoring you in magic, you can visit her to begin your magic training. Test Divination >1 to comment on her methods. Regardless of the outcome, +1 Afraid.
After Week 9 Edit
If Selene is you magic mentor and Joslyn barred Elodie from getting your Lumen crystal, speak to Selene and she will offer to deal with the treasury guards. If refused, this event will be repeated if Week 18 passes without obtaining the crystal. See Week 18 for the outcome.
After Week 18 Edit
If a squire was murdered and Selene is your magic mentor, you can visit her to discuss the event. Pass a Sense Magic >0 check (cannot be failed), then a Lore >100 check to learn something (+1 Pressured), otherwise you'll be brushed off (+1 Yielding).
If Elodie asked Selene to deal with the treasury guards, she gets her Lumen crystal at the cost of the guard's lives, Joslyn's trust and +1 Depressed.
After Week 20 Edit
If Julianna has escaped prison and Elodie spoke to Brin, Selene will evade the guards and become a fugitive herself.
If you sent the wife-killer to Selene, visit her to discover how she deals with rogue Lumen.
After Week 17 or Week 21 Edit
If Elodie obtained a spare Lumen crystal last week, you can visit your magic tutor to question her about it. +1 Pressured. If Selene is your tutor, pass a Lore >70 for more information; this may unlock additional choices during Week 36.
Julianna is Elodie's mentor and Sense Magic is >80 Edit
Selene's status as a Lumen will be revealed by Attending Services with Sense Magic >80, then speaking to Julianna during the weekend. This makes her available for the magic ritual of Week 34, otherwise Julianna will never divulge her secret.
Belying her delicate appearance, Selene is a ruthless person unafraid of shedding blood for the greater good of Nova. Unlike her partner, Selene is brutally honest about the horrors that the abuse of magic can bring, and treats Elodie as an adult and a queen and thus capable of fully shouldering the burden of resposability.
She's capable of committing horrible acts (such as killing the treasury guards or rendering the murderer comatose) without a shed of regret if they serve a greater purpose.
She's taken an oath of keeping her powers secret, but she will break said oath if the situation calls for it, such as offering to become Elodie's Lumen mentor or being called for the magic ritual. However, if Elodie doesn't discover Selene's status by herself, she will remain hidden.
All evidence points to her relationship with Julianna being very loving. Elodie may spot them holding hands in the garden, and they will get married and adopt Briony in one epilogue. If Julianna is imprisoned she will request her freedom, and if Elodie has Julianna marked as an outlaw then Selene will completely turn her back on the crown.
Selene is a powerful Lumen despite keeping her powers secret for most of her life, and has an affinity for water-based magic. Some examples are her usage of water for divinations, locating the position of the kraken in the novan seas, and drowing the treasury guards with summoned water and poisoning the murderer with salt water. This isn't counting what she can do if aided by other Lumen.
Besides her magic, Selene is an experienced priestess with mastery over divination, meditation and lore knowledge, which she will teach to Elodie as her tutor. Given her career she may have been already initiated in the mysteries of the priestesses.
- She seems to be something of a homage to Sailor Neptune, considering her water-based powers, psychic abilities, personality, femme appearance and relationship with Julianna (herself a homage to Sailor Uranus). Adittionally, Mazomba (the duchy she hails from) is also the name of a crater on Triton, a moon of Neptune.
- A special conversation with Brin (only seen if romanced) reveals that she used to be in a relationship with Julianna, which the latter broke off for a relationship with a priestess. It's pretty much evidenced that said priestess is Selene.
- Passing the Lore check when asking her about extra Lumen crystals reveals that she has inherited Mazomba's ducal crystal. After the Doomshadow fell, the crystal was protected by a temple, then passed to a priest skilled in scrying and down his family line.
Selene is the name of the greek personification of the moon, and also an alternate name for the Moon of Earth and a minor planet orbiting the sun. Besides the mythical theme, this ties with Selene's powers, as it's believed that the Moon has an effect over the ocean tides.