Jill is very reserved and intelligent, possessing a very high opinion of herself, as well as a persistent and demanding presence, seen when she apparently continuously contacted BoJack to remind him of something when her deadline wasn't met and refusing to stop until it was finished.
She is shown to be very sexually motivated, as shown with her former relationship with Cuddlywhiskers, as well as her repeated attempts to have BoJack retrieve a graphically sexual letter she wrote to Cuddlywhiskers for "sentimental" reasons.
She is shown to have a softer side, as shown in her own self-indulgence, as she knitted herself a spider-silk sweater, and in her interactions with Cuddlywhiskers, where she's seen putting on an act to seduce him.
Jill is an adult female black widow spider.
According to the model sheets, she is slightly under 5 ft tall with a hunched posture.
She has grey skin, a red hourglass on her chest, six long arms, and two legs, which matches the limb count of a spider (eight), eight eyes with indigo eyeliner applied to each, plump lips with blue lipstick, sharp teeth, and what appear to be two sets of pedipalps on her face.
Her build is very mechanical, having a broad body shape, while also possessing thin limbs. Despite this, her waist is very large, as widow spiders have very big abdomens when compared to their heads.
Her style seems to be in line with modern hipster-esque tropes. She wears a fuchsia beret, a black long-sleeved top with a white lace-plaid pattern on it and a deep violet belt, a blue skirt with black leggings underneath, and purple, indigo, and light red heels.
In 2007, she wore a dull, greyish-burgundy wig styled into a bun, a pink sweater-jacket with a tied lace, a dark lavender skirt with thin white lines on it, a fuchsia belt, and matching fuchsia high heels. She wears the same lavender eyeliner and magenta lipstick.
Not much is revealed about Jill's past, other than the fact that she was once acquainted with writer Cuddlywhiskers. From her brief appearance, it's assumed that she and Cuddly had a sexually aggressive relationship, as she's first seen behaving like a maid, which is followed by a lusty bout of disobedience after being yelled at by Cuddly.
What is known is how she met BoJack, as she was bringing some water to Cuddlywhiskers and BoJack, prompting Cuddly to introduce her.
She is now a playwright in NYC, New York. One of her plays, that is shown in her debut episode, is The Tragedie of Greg Kinglear.
Jill is first mentioned by Princess Carolyn in Yes And when she informs BoJack that he got an offer from Jill Pill for him to act in her off-Broadway play in New York before the movie comes out. BoJack says that it sounds like something he should be doing right now, and he accepts the role with excitement.
In Out to Sea, Princess Carolyn calls BoJack and tells him that she keeps getting calls from New York playwright Jill Pill, saying she really wants to talk to him and that apparently she worked on his show—not Horsin' Around, his other show, to BoJack's shock as he realizes what show she means.
BoJack goes to lunch with Jill afterward. She asks if he's talked to at all Cuddlywhiskers, and tells him to when he returns to L.A., as she hasn't heard from him in months because he owes him. Jill says she's ending her play, and she wants him for her next project. BoJack tells her that he's not the type of guy that does edgy things and how he's trying to win an Oscar and thinking about his legacy now. Jill tells him that nothing lasts but BoJack says that if he wins an Oscar then he'll be remembered.
In The BoJack Horseman Show in a flashback from 2007 Cuddlywhiskers then introduces BoJack to his assistant, Jill, and the two have a "special relationship." He then continues to explain to BoJack that he's trying to do something different and create something that lasts, and to send him an e-mail when he wants to stop being "The Horse from Horsin' Around."
In BoJack Kills BoJack is attending a non-specific, inoffensive version of a winter holiday play referred to as, "An All-Inclusive, non-denominational winter day pageant" which he was attending due to the parents present being Oscar voters at Rounded Corners Prep.
In the middle of the play, he is contacted by the playwright Jill Pill. Jill requests that BoJack contact Cuddlywhiskers, a popular director and Jill's former lover, to retrieve a letter that has holds "sentimental value."
As they're driving to their next appearance for the Oscar campaign, BoJack asks Diane permission to stop and pick up Jill's letter, though Diane retorts that she just wants to make their next appearance and then go home. BoJack attempts to salvage conversation with her by asking why he hasn't seen her in a while. She responds with quips about her marriage and job, while BoJack adds in that she's also avoiding him.
She begins saying that she and BoJack are similar in several ways. She notes that, while that is great by itself, it's also dangerous and can bring out the worst in both of them if they're together. She adds that she's trying to get her life back together, and requests that she and BoJack only get together under professional circumstances. BoJack accepts the terms, only to reveal that he went to retrieve Jill's letter from Cuddly's home against Diane's requests, passing it off as an "accidental detour."
In That's Too Much, Man!, during his blackout on a drug bender, BoJack has a flashback (where everything is shaking around him) to Thanksgiving 2007, at Cuddlywhiskers's house. Cuddlywhiskers just got off the phone with the network executives, and they had told him the latest episode of The BoJack Horseman Show had gotten the lowest ratings yet.
He tells BoJack he still believes their show has an audience, and they should try to get a guest star to boost ratings. Jill Pill recommends Sarah Lynn. BoJack is uneasy about this, as she's “the world's biggest pop star" and he hadn't spoken to her since Horsin’ Around ended. Cuddlywhiskers convinces him anyway, even saying BoJack was "like a father to her."
- Start Spreading The News (official debut/first on-screen appearance)
- The BoJack Horseman Show
- BoJack Kills
- That's Too Much, Man! (flashback)
- She is voiced by Mara Wilson, who is best known for playing Matilda in the film of the same name.
- The red hourglass on her chest is a possible reference to Marvel's Black Widow.
- Her name appears to be a play on the phrase "take a chill pill." Appropriately, she usually speaks in a rather mellow tone.