She was widely known for designing dust jackets for Lost Generation writers in the 1920s and early 1930s, including cover art for the first editions of Ernest Hemingway's The Sun Also Rises and A Farewell to Arms, as well as F. Scott Fitzgerald's All the Sad Young Men, which were published by Scribners.

In 1921, The New York Times Book Review and Magazine published a reprint of her etching, The Boudoir, and noted her other work featuring "trees and dancers resembling one another, pillowy anatomies", and "Rosalindish daring and gayety and irresponsibility".

[18] Her Allegretto, a characteristic study of three dancers, was highlighted by The New York Herald as one of the "most noticeable" prints at the "American Etchers Salon of 1922" exhibit at the Brown-Robertson Gallery.

[23][16] Editor Maxwell Perkins wrote that after persuading Charles Scribner's Sons to sign a contract with controversial up-and-coming writer Ernest Hemingway in February 1926, he chose Cleon to design the dust jacket for The Sun Also Rises,[24] to appeal to "the feminine readers who control the destinies of so many novels".

[25] For The Sun Also Rises, Damianakes etched a Hellenic figure lounging in front of a small desiccated tree, head bent, wearing a billowing robe exposing her left thigh.

"[26] Author Leonard Leff writes, "What Cecile B. de Mille's 'studies in diminishing draperies' had done for Hollywood, the artist Cleonike Damianakes had done for Scribners: 'Cleon' had made sex respectable.

"[26] Literary historian Catherine Turner argues that by associating his "experimental" works with images recalling ancient Greece and Rome, Perkins was "[connecting] Hemingway with a long tradition of Western culture".

[26] One of her initial designs featuring helmets and artillery was rejected outright by Perkins, who explained that Scribners wanted to distinguish it from the war novels that were flooding the market.

[24][29] In Cleon's version, Venus is a mostly nude winged female reclining with her eyes closed, while Mars is a male figure wearing only a loin cloth, who rests his head on one arm, holding a broken axle with the other.

[29] Hemingway did not like her cover art for A Farewell to Arms, and was "scathing" in his criticism to Perkins about its "lousy and completely unattractive decadence i.e. large misplaced breasts etc ...the awful legs on the woman or the gigantic belly muscles".

[34] The fact that Damianakes designed the book jackets for All the Sad Young Men, The Sun Also Rises, and A Farewell to Arms earned her the reputation as a creator of cover art for the Lost Generation.

[23] In 1928, he won a prize for best non-fiction book jacket of the year for The American Adventure: A History of the United States by David Saville Muzzey, published by Harper & Brothers.