Arachine, Daughter of Lolth

Magic through Beauty. Creatures who aren't attracted to females are immune to Arachine's spells (except Bestow Curse), and her Charisma score is considered 25 when interacting with males (included in spellcasting)

Divine right. Drow are inclined to help Arachine and any kind of spider will do anything she says. With a DC 25 Persuasion check she can persuade Lolth to force a Drow to follow Arachine's order (the Drow will be unaware).

Subtle Charming. When Arachine uses magic to influence a creature's mood, they are completely unaware of it. She also ignores immunity to being charmed and advantage on saving throws against it.

Spider Form. Arachine can transform into a giant spider and back at will, without a bonus action during her turn or between other creatures' turns.

Fey Ancestry. Arachine has advantage on saving throws against being charmed, and magic can’t put her to sleep.

Innate Spellcasting. Arachine's spellcasting ability is Charisma (spell save DC 18). She can innately cast the following spells, requiring no somantic or material components:

At will: friends, charm person, heroism,  command, sleep

3/day each: enthrall, detect thoughts, calm emotions, hold person, suggestion, zone of truth, bestow curse

1/day each: dominate person(as if it was an 8th level spell slot),  geas, modify memory, mass suggestion(as if it was an 8th level spell slot), antipathy/sympathy(only sympathy)

Sunlight Sensitivity. While in sunlight, Arachine has disadvantage on attack rolls, as well as on Wisdom (Perception) checks that rely on sight.

Dark touch. Melee Weapon Attack: +4 to hit, reach 5 ft., one target. Hit: 2 [rollable](1d4);{"diceNotation":"1d4","rollType":"damage","rollAction":"Dark touch","rollDamageType":"necrotic"}[/r, On a hit, the target becomes friendly towards Arachine, is Charmed by her, and protects her in any way possible, except if it will surely be suicide if it fails a Wisdom saving throw (DC 15). It makes the saving throw with disadvantage if it is already Charmed by Arachine, and advantage if it knows or highly suspects she is trying to control it. The attack is not obvious it is an attack, so the attack roll automatically succeeds if the target isn't actively trying to not get touched. 

Damsel in distress. If on 1 hit point, Arachine can use her bonus action to cast dominate person without expending her 1 use per day and it doesn't get advantage on the saving throw if Arachine or her allies are fighting it. If it fails the saving throw, Arachine gets 5 temporary hit points and the effects of dominate person also happen.

Insistance. When a creature succeeds on a saving throw against one of Arachine's spells, she can use her reaction to make it fail, by expending 1 Insistance point, of which she has 4.