Iris

Iris is the the Incubus King's long-suffering secretary. She handles much of the running of his empire, as well as trying to rein in the worst of his excesses. Despite serving as an administrator, she is a capable mage and can be very dangerous when she is acting strategically - twice so far she had sprung unpleasant surprises to Simon and his allies.

Story
Iris is first shown, without being named, during one of the cutscenes after the prologue, informing the Incubus King that he has run out of elf sluts and trying, and failing, to guide his mind away from his weird fetishes and towards more productive actions, such as conquering the world.

She again appears in a cutscene during Chapter 2, when she reminds her boss that he doesn't rule Ardoheim yet. Much to her dismay, this prompts him to order a hasty invasion, a decision that will have great consequences to Simon and those around him.

Iris's actions in the invasion itself are off-screen, but have a great impact: she has a pair of seeds of corruption dropped to soften up the defender's resistance. The first seed lands near the camp of Carina's men, and after Carina's semi-successful attempt at purifying it she becomes infected with its corruption, which results in her having sex with Simon and joining his group. The second seed is dropped after the Horde is successfully repulsed, and its cunning positioning forces Simon to use his Incubus King powers, attracting the attention of other shard-bearers. This in turn results in Simon being taken hostage by the Empress of the Orgasmic Empire and the temporary split of the party into three in his absence.

During the Gathering, Yarra's group has the opportunity to interact with Iris, who has unsurprisingly accompanied The Incubus King. The first conversation is the most interesting, as Iris shares her frustrations with her boss. She explains that she is loyal not personally to him, but to her people - the succubi under his rule. Yarra tries to insinuate the possibility of a possible successful rebellion, but it seems that Iris doesn't believe in fairy tales anymore... About other masters being better, she acknowledges their existence but she is set firmly in hard reality. Also, Iris shares some alarming news about Riala.

In Chapter 3, Iris again appears in a cutscene in The Incubus King's throne room, this time reporting about the Doom King's successful conquest of Yhilin. Simon finds out the consequences of that conversation later, when during negotiations between the queens of Darghelon and Gheldaron, a seed of corruption was unleashed upon them. But then the Incubus King lost the interest, and the seed and the troops that brought it there are left to their own devices. Iris goes primarily to rescue her troops and secondarily to retrieve the seed of corruption. Simon and the party strike a deal to help Iris and her succubi leave the elven kingdoms with as little trouble as possible.

She is next seen when The Incubus King decides to conquer the continent again and declares war, totally unsurprised and having already made preparations for the inevitable conflict.

The initial salvo of the Third Arclent War is at her command, a large amount of seeds of corruption directed not any one country, but all of them. During the events of the war, she has some appearances as we see glimpses of what is happening in the enemy's headquarters. She seems to be on top of things, but she also shows a healthy respect for her opponents as she acknowledges that she can't be ready for all the surprises that the enemy is planning. She keeps her loyalty until the moment that The Incubus Superking announces his new secret weapon: the Unsuccubi. At that point, he crosses a line.

So when the chance to jump ships literally arrives at her door, she doesn't take much convincing from Simon and Riala.

In Simon and Iris's first reunion after the Incubus Emperor is defeated, she says the following line and it says a lot about her character:

Relationship points
Maximum affection is 100, at which you can have a conversation with the harem girl that will lock her affection there.

Iris is deeply dedicated to the succubi she leads, and as such her RP gains and losses are focused around aiding the newly formed Chalice States as well as succubi in general, limiting the damage done to the civilian population during the war, how much the succubi view you as their savior and how much you help them.

Base value: 30.

Maximum legit value: 100 (+10 leeway).
 * choosing "Sabotage as much as possible" at Entrance Tunnels.
 * Up to when infiltrating the Tower of Mist, from stealth and not looting storerooms. With the best result, the elite succubus will say "You were actually amazingly sneaky, getting in here! I mean, a fight and an alarm, but I can take care of those!"
 * choosing "Begin sabotage campaign" at Tower of Mist in Gasm Falls.
 * if you do well enough at Bloody Spire that later when meeting Aka, Orcent says "Most importantly, the orc hordes have agreed to serve the Doom King."
 * if you encountered 10 succubi in Incubus Castle who left without fighting. (Requires very low IKD morale.)
 * Up to from morale of the former Incubus King's Domain after winning the war, or down to.
 * sending economic aid to repair damage to the Chalice. (Only requested if you chose to sabotage it).
 * sending economic aid to help the Chalice States feed surrounding regions temporarily, in Conference Chamber during war aftermath.
 * using political capital to help the Chalice States deal with outsider merchants, in Conference Chamber during war aftermath.
 * using political capital to make the Church of Ivala stop persecuting Ivalan succubi, in Conference Chamber during war aftermath, OR unmissable if negligible persecution occurs due to sufficient religion influence.
 * talking to black-haired succubus with marriage idea, in Conference Chamber during war aftermath. (Only available with low IKD morale.)
 * sending military forces to police human bandits on Yhilin's southern border. (Only requested with high instability across the continent.)
 * investing in expanding Yhilini trade into former IKD territories. (Only available with low IKD morale.)
 * investing in Gasm Falls shop. (Must have been previously contacted.)
 * investing in Chalice States trade.
 * Unmissable from Chapter 4 start.
 * building second well in Headquarters Courtyard.

Affection titles

 * 0 Secretary
 * 50 Assistant
 * 75 Personal Assistant
 * 100 Beloved Assistant

Scenes
On-demand:
 * Special Surprise - Simon receives a surprise and a morning blowjob. Unmissable at the start of Chapter 4.
 * Iris + Megail - Iris and Megail collaborate on a project. Rest in Headquarters. 
 * Iris + Megail Anal - With the success of their previous partnership, Iris and Megail invest in a new venture. Rest in Headquarters. Requires Iris + Megail.
 * Working - Iris gets her administrative fetish fulfilled. At 50 affection and above.
 * Meeting - Iris helps some succubus petitioners relax during a meeting. At 75 affection and above.
 * Seduction - Iris reminds Simon that she is a succubus. At 100 affection.