A Seattle-based agent and agency founder who built her career on graphic novels and comics, now running a boutique full-service shop that champions illustrated storytelling across the age spectrum.
In brief
Siess founded her own agency in 2020 after demonstrating she could close deals with all five major publishing houses within her first year as an agent — that is a rare commercial track record for someone at any career stage.
Her sales record is heavily weighted toward graphic novels and illustrated middle grade: Bree Paulsen's Garlic series and Sweeney Boo's witchy YA graphic novels are the clearest signals of where her taste is sharpest and her editorial relationships deepest.
Client Alexandra Rowland represents a genuine outlier — adult prose fantasy with no pictures at all — suggesting Siess will occasionally take on prose fiction when the voice is distinctive enough, but this appears to be the exception, not the rule.
Two of her represented authors (Sweeney Boo and Bree Paulsen) have produced multiple titles, confirming she builds long-term career partnerships rather than one-and-done deals.
Writers of middle grade and YA graphic novels with a cozy-but-spooky, friendship-forward, or magic-inflected tone should consider her a top-tier match.
Lately
Her agency's current page positions BSCM as representing 'some of the biggest names in graphic novels and comics,' reinforcing that illustrated work — particularly graphic novels — remains the defining pillar of her list heading into 2026.
What Britt is looking for
This is the heart of her agency's identity and the category where she has the deepest editorial relationships and the strongest sales record. She is drawn to illustrated narratives with emotional resonance — friendship, identity, magic, and coming-of-age themes all appear repeatedly across her client work. Cozy-but-spooky tones, witchy premises, and character-driven stories are well-represented on her list.
Her agency's scope includes picture books and children's illustrated work more broadly, with a noted emphasis on illustration. Given her background, projects that lean heavily on visual storytelling or come from author-illustrators are a stronger fit than text-only picture book manuscripts.
Illustrated middle grade — whether graphic novel format or heavily art-driven chapter books — sits squarely in her wheelhouse. Her sales in this space show a preference for humor, warmth, magic, and stories about friendships navigating social pressures.
Her representation of Alexandra Rowland's adult prose fantasy demonstrates she is capable of and interested in this space, but it appears to be a selective, case-by-case interest rather than an active priority. Standout voices with a strong sense of narrative and political intrigue may warrant querying, but writers should not expect this to be her main lane.
Not the right fit
On Britt's list
Taste fingerprint
How to query Britt
Lead with format first: clearly identify your project as a graphic novel, illustrated middle grade, picture book, or other visual-forward format — this is the primary organizing principle of her list.
If you are querying a graphic novel, include sample art or indicate the illustrator's name and credentials early; she represents illustrators as well as authors, and visual execution is central to her acquisitions.
Study the emotional register of her confirmed sales — cozy, warm, magic-inflected, friendship-centered, with a hint of spooky — and reflect where your work fits within or adjacent to that tone.
If you are pitching a multi-book series or sequel potential, say so. Multiple clients have produced two-book runs with her, suggesting she values projects with franchise potential.
For adult prose fiction, the bar appears high and selective; frame your query around what makes the voice and narrative stakes exceptional rather than leading with genre alone.
Verify her submission form is still active and review any current guidelines before querying — status was confirmed open as of late May 2026, but policies can change.