Kiss me liar and this are novels written by the same author, there's actually a long list of novels from the same universe.
The different novels of this author (including roses and champagne) are mainly picked by different illustrators/artists. So it's not that the style improved, it's that it's a different person drawing, but the same person wrote both
Related Series
Kiss Me, Liar (Shared Universe)
Kiss Me if You Can (Shared Universe)
Desire Me If You Can (Shared Universe) Chase Miller + Josh
Eat Me Up If You Can (Shared Universe)
L*ck Me If You Can (Shared Universe)
Kiss the Scumbag (Shared Universe)
Kiss The Stranger (Shared Universe)
Kiss My Grits (Shared Universe)
Run Away If You Can (Shared Universe) Nathaniel Miller +
HELP IT'S THE SAME WORLD IN KISS ME LIAR. IT WAS LATE BEFORE I REALIZED IT. THE ART WORK IMPROVED OMGGG