Evangelion 303: Asuka is the main fanservice provider in this story. She shows up naked frequently and the author has drawn dozens of Asuka pictures where she is naked or scantily clad.
Eclipse and Pauline from the Tamers Forever Series. Both of them are described wearing rather ...flattering outfits, and are rather flirtatious in nature. That being said however, they are still fully developed characters besides just being sex appeal.