I hope you play the game first before trying these, but here they are. Generally you shouldn't need a whole lot more help than these stat boosts to advance through the game; there's plenty of hidden stuff but not a lot of tricks that are needed to learn if you've got all the stats.
Version 1.7.0: (These will only work on v1.7.0 onward.)


kenjipluscheat - boosts each of Kenji's stats by 1
chaching - adds 1000 gil
rebelwithoutcause - raises rebellion by 6 (I think the previous version of this cheat wasn't working, but now it should)
hubbahubba  - raises all the maids' lust by 10 
awwsweet - raises all the maids' love by 10
vsshortcut <harem code> - just add the harem code without the <> symbols as a separate word after the cheat. This teleports you to the victory suite. Don't do it if you haven't seen the harem ending, though, because you'll be missing out big time! 

Extra cheats in v1.10.0:

spoitspoit - set orgasm points to 99 (in sex scenes)
raisemaidstats - raises all maids' hand, mouth & eye by 1
L F A T R M R D H-harem code