Keiraku no Houteishiki Level-C

Okane ga Nai and Level C are essentially the same story told differently. In both cases we have a rather thin plot involving a strong shounen-ai element that includes sex as rent, as odd as it may seem. While not overly graphic in terms of content both titles have no qualms in being pretty in-your-face. Okane ga Nai has more angst and occasionally violent while Level C is sheer fluff but they are remarkably similar.  

my sexual harrassment is a great title for a yaoi noob i also recomend checking out level c 

If u like Level-C u'll like Gravi. Gravi has light BL while Level-C has a hard BL content. Both have a somewhat unrealistically cheerful attitude and can't 4get both have the main characters living in the same house! So let your imagination take hold! ~BunnyYamato~